All 64 people aboard an American Airlines jet that collided with an Army helicopter were feared dead in what was likely to be the worst U.S. aviation disaster in almost a quarter century, officials said Thursday.

At least 28 bodies were pulled from the icy waters of the Potomac River after the helicopter apparently flew into the path of the jet late Wednesday as it was landing at Ronald Reagan National Airport near Washington, officials said. The plane carried 60 passengers and four crew. Three soldiers were aboard the helicopter.

“We don’t believe there are any survivors,” said John Donnelly, the fire chief in the nation’s capital. “We are now at the point where we are switching from a rescue operation to a recovery operation.”

The plane was found upside-down in three sections in waist-deep water, and first responders were searching an area of the Potomac River as far south as the Woodrow Wilson Bridge, roughly 3 miles south of the airport, Donnelly said. The helicopter wreckage was also found. Images from the river showed boats around the partly submerged wing and the mangled wreckage of the plane’s fuselage.

If no one survived, the collision would be the deadliest U.S. air crash since 2001.

There was no immediate word on the cause of the collision, but officials said flight conditions were clear as the jet arrived from Wichita, Kan., with U.S. and Russian figure skaters and others aboard.

“On final approach into Reagan National, it collided with a military aircraft on an otherwise normal approach,” American Airlines CEO Robert Isom said. “At this time, we don’t know why the military aircraft came into the path of the … aircraft.”

President Donald Trump opened a White House news conference after the crash with a moment of silence honoring the victims, calling it an “hour of anguish” for the country.

But he spent most of his time casting political blame, lashing out at the Biden administration and diversity efforts at the Federal Aviation Administration, saying they had led to slipping standards — even as he acknowledged that the cause of the crash was unknown.

Without evidence, Trump blamed air traffic controllers, the helicopter pilots and Democratic policies at federal agencies. He claimed the FAA was “actively recruiting workers who suffer severe intellectual disabilities, psychiatric problems, and other mental and physical conditions under a diversity and inclusion hiring initiative.”

Inside Reagan National Airport, the mood was somber Thursday morning as stranded passengers waited for flights to resume, sidestepping camera crews and staring out the terminal’s windows at the Potomac, where recovery efforts were barely visible in the distance.

Aster Andemicael had been at the airport since Wednesday evening with her elderly father, who was flying to Indiana to visit family. She spent much of the long night thinking about the victims and their families.

“I’ve been crying since yesterday,” she said, her voice cracking. She recalled seeing a young woman frantically running through the airport around the time of the crash, possibly in search of a loved one who would never return.

“I pray for them,” she said. “This is devastating.”

Flights resumed at the airport shortly after 11 a.m. Thursday. But many flights had been canceled, and airport information boards were covered in red cancellation messages. Other flights were delayed until late morning or afternoon.

Transportation Secretary Sean Duffy said, who was sworn in earlier this week, was asked if he could reassure Americans that the United States still has the safest airspace in the world.

“Can I guarantee the American flying public that the United States has the most safe and secure airspace in the world? And the answer to that is, absolutely yes, we do,” he said.