As a military offensive by Turkey into Syria enters its third day, aid agencies are increasingly concerned. An estimated 100,000 civilians in northeastern Syria have been displaced, at least one displaced-persons camp was relocated out of the line of fire, a front-line hospital was abandoned and critical water infrastructure was taken out of commission, according to the United Nations. All of this is exacerbating a humanitarian crisis that was already one of the world’s worst.

On Wednesday, Turkish ground and air forces commenced a series of assaults against a Syrian militia of the Kurdish ethnic group, which had been an American ally in the fight against ISIS but is viewed as a terrorist organization by the Turkish government.

Until this week, northeastern Syria near the border with Turkey had been a refuge of relative safety for people fleeing violence in other parts of the war-torn country. Humanitarian relief agencies have been providing food, water, medicine and other lifesaving aid to more than 90,000 internally displaced people there as well as more than one million other residents who had lost access to social services because of the conflict.

Now, the towns and camps where those people are living are suddenly on the front lines of a new, unpredictable combat operation.

On Friday, local Kurdish government officials announced plans to immediately evacuate 7,000 internally-displaced persons from one camp, al-Mabrouka, that they said had been hit with artillery shells. In the border town of Tal Abyad, hospital workers were forced to abandon at least one hospital because of shelling, according to Médecins Sans Frontières.

And according to UNICEF, a water pumping station that serves 400,000 people was attacked late Thursday and taken out of service.

“The situation on the ground is becoming increasingly dire, and once again, civilians are paying the highest price,” Misty Buswell, Middle East policy director at the International Rescue Committee, said in a statement Friday afternoon. “There are already reports of [water] shortages in some rural areas, with possibly much worse to be seen in a few days if services are not able to get back up and running soon.”

UNICEF, IRC, CARE International and some other groups have temporarily suspended services in the border area, evacuated foreign staff and asked local staff to remain home.

If humanitarian services continue to be cut off, the situation could quickly worsen, Karl Schembri, a spokesperson for the Norwegian Refugee Council, told NPR.

“These people are already under extreme duress,” he says. “There are a lot of displaced-persons camps there that are completely dependent on aid services, and if they are cut off, that would put lives at immediate risk.”

By Friday, Turkish troops had captured several Kurdish villages and blocked roads between others, The Associated Press reported. Riots broke out at Al-Hol, a camp near the border that was used to detain the wives and children of suspected Islamic State fighters.

Many of the displaced people are fleeing south, deeper into Syria, says Aleksandar Milutinovic, Syria country director for CARE. As the situation unfolds, it may become difficult to keep them from unintentionally winding up back in harm’s way, squeezed between the Turkish offensive and the civil war.

“We’re trying to understand where they can find safety,” he says.

Meanwhile, Milutinovic says, humanitarian groups fear that the offensive could disrupt aid supply lines, which have been coming into Syria from Iraq.

“We really want to keep those lines open, so we don’t face a shortage of food and other supplies,” he says. “If the conflict continues, we expect those things will be depleted very fast. And we are very concerned about medical facilities. Unfortunately in any conflict zone, some doctors and medical employees have to leave, leaving very few resources to care for those people.”

If and when the military campaign settles, there may be further humanitarian challenges ahead. Last month, Turkish President Recep Tayyip Erdoğan announced plans to return up to 2 million Syrian refugees currently living in Turkey to so-called “safe zones” in conquered territory in Syria. That plan was met with outcry from human rights advocates, who fear that such zones would be inaccessible to humanitarian workers and could become a backdrop for human rights violations by Turkish armed forces.

The plan “defies all norms of international law and humanitarian law, and it’s outrageous,” Stephen Morrison, director of the Global Health Policy Center at the Center for Strategic and International Studies, a Washington think tank. “And it’s going to be a complete debacle for public health.”

A quick-moving wildfire is churning through the foothills of Southern California, forcing local authorities to issue mandatory evacuations for some 100,000 people in the San Fernando Valley north of Los Angeles.

The blaze, which officials have named the Saddleridge Fire, ignited late Thursday in the city of Sylmar. By Friday morning, it had torched roughly 4,700 acres, according to the latest alert by the Los Angeles Fire Department.

“This is a very dynamic fire,” Los Angeles Fire Chief Ralph Terrazas said at a Friday morning press conference.

At least 25 structures have been destroyed and more property assessments are planned throughout the day.

Jacob Margolis of member station KPCC described the scene from a first responders staging area at Hansen Dam, located in the city of Lake View Terrace, not far from the fire line.

“There are bulldozers, trailers,” Margolis told NPR’s Morning Edition on Friday.

“Really everyone is just trying to coordinate and figure out how to tackle the fires, especially before they creep into the neighborhood. And they’ve been doing that all night,” he said.

Emergency officials say one civilian went into cardiac arrest and died at the hospital, and one firefighter sustained a minor injury to his eye. The officials did not provide details about those cases.

No cause for the fire has been determined. Terrazas said emergency officials received the first reports of the fire around 9 p.m. Thursday and that it was located near the 210 freeway at the Yarnell Street exit.

“Our first arriving companies reported significant fire with multiple homes threatened,” Terrazas said. “We went into an aggressive offensive attack while simultaneously setting up our structure protection.”

LAFD reports the fire is at 0% containment, with more than 1,000 firefighters assigned to combat it. Personnel from the Los Angeles Police Department, Los Angeles County Fire Department and U.S. Forest Service are on the scene, helping with the effort.

“Super scoopers and the Sky Crane are in operation this morning,” LAFD said.

Strong Santa Ana winds, coupled with the area’s dry chaparral landscape, have helped fuel the fire. The flames have forced the closure of several miles of the 118 and 210 freeways. Evacuation orders affect communities on both sides of Interstate 5 in the northernmost city in Los Angeles County.

The National Weather Service said a wind advisory and a red flag warning are in effect.

“A moderate to strong Santa Ana wind event will continue to bring dangerous fire weather conditions to most of Los Angeles and Ventura Counties through late Friday afternoon,” NWS said in its latest alert.

The agency adds, “Wind gusts between 45 and 55 mph are expected across coastal and valley areas, with gusts between 55 and 75 mph in the foothills and mountains.”

NWS warns that windy, dry conditions will bring the “potential for very rapid fire spread, long range spotting, and extreme fire behavior.”

Earlier Friday, LAFD tweeted that some evacuation centers like one at Granada Hills Recreation Center were full, but it added that others were opening up.

For days, California utility companies have been preemptively cutting off power out of fear that high wind gusts could blow power lines into trees, sparking dangerous fires.

Southern California Edison cut off power to more than 21,000 customers under its Public Safety Power Shutdown in Kern, Los Angeles, Riverside, San Bernardino and Ventura counties.

The utility also said it is considering shutting off an additional 223,000 customers’ power.

Gas utilities are also taking action. As the LAist news site reports:

“SoCalGas officials said personnel at their gas storage facility at Aliso Canyon had been evacuated by fire authorities. In an email responding to questions, they said multiple fire engines and firefighters from the city and county were fighting the fire “in and around the Aliso Canyon facility.”

Earlier in the week PG&E, the state’s largest utility, began proactively shutting off power to roughly 800,000 customers in Northern and Central California, impacting nearly 2.5 million people, according to one estimate.

Updated 11:20 a.m. ET

As part of the congressional impeachment inquiry into President Trump, Marie Yovanovitch, the former U.S. ambassador to Ukraine who was recalled from her post by Trump, is testifying Friday before three House committees in a closed-door deposition.

The career diplomat was recalled from her post in May after criticism from some Republicans, including Donald Trump Jr., the president’s eldest son, that she was not supportive of the administration’s policies. She was appointed by President Barack Obama in 2016 and confirmed without any controversy by the GOP-led Senate.

She has emerged as a key fact witness in the House Democrats’ investigation following a whistleblower complaint about Trump’s telephone call with Ukrainian President Volodymyr Zelenskiy on July 25 that triggered the inquiry.

Investigators are interested in learning details about Yovanovitch’s interactions with the president’s personal lawyer Rudy Giuliani and others seeking a Ukrainian investigation into former Vice President Joe Biden and his son Hunter’s business interests in one of the country’s largest gas companies.

Trump referred to Yovanovitch as “bad news” to Zelenskiy in the White House account of the conversation released last month.

Earlier this week, the State Department blocked the U.S. ambassador to the European Union, Gordon Sondland, from testifying. After Congress issued a subpoena, Sondland said he would defy the State Department and testify Thursday.

An attorney for Sondland said in a statement that he has “at all times acted with integrity and in the interests of the United States. He has no agenda apart from answering the Committees’ questions fully and truthfully.”

The statement also noted that Sondland will not release documents that Congress is requesting, however, and that it’s up to the State Department to do so.

“By federal law and regulation, the State Department has sole authority to produce such documents,” per the statement, “and Ambassador Sondland hopes the materials will be shared with the Committees in advance of his Thursday testimony.”

Sondland flew from Brussels to Washington to voluntarily answer questions about text messages between him and the senior diplomat at the U.S. Embassy in Ukraine, Bill Taylor, about whether military assistance was being conditioned on investigations related to political campaigns.

Earlier this week, White House counsel Pat Cipollone sent a letter to House Speaker Nancy Pelosi, D-Calif., and the chairs of the three committees saying the administration would not cooperate with document or testimony requests, arguing that the inquiry “lacks any legitimate constitutional foundation” and is simply an effort to “nullify the outcome of the democratic process” by reversing the results of the 2016 election and influence the upcoming 2020 election.

The whistleblower complaint released Sept. 26 says that Yovanovitch had criticized a former Ukrainian prosecutor’s “poor record on fighting corruption.” The same prosecutor, Yuriy Lutsenko, spread rumors about the Biden family and about Ukraine’s “purported involvement in the 2016 U.S. election,” as the whistleblower notes.

Lutsenko accused Yovanovitch of obstructing Ukrainian investigations and providing the U.S. with “evidence” of wrongdoing.

The whistleblower added that Lutsenko “later walked back” many of his allegations.

Despite that, the whistleblower cites reports that Giuliani met with Lutsenko twice, once in New York and once in Warsaw, Poland, earlier this year. Trump himself, as the whistleblower also notes, called Lutsenko’s allegations “big” and “incredible” on Fox News and said “that the attorney general ‘would want to see this.’ “