All 67 people on board the plane and the helicopter were killed.
An American Airlines regional jet went down in the Potomac River near Washington, D.C.'s Ronald Reagan Washington National Airport after colliding with a U.S. Army Black Hawk helicopter on Wednesday night, with no survivors.
Sixty-four people were on board the plane, which departed from Wichita, Kansas. Three soldiers were on the helicopter.
The collision happened around 9 p.m. when the PSA Airlines Bombardier CRJ700 regional jet was on approach to the airport.
President Donald Trump called the crash a "tragedy of terrible proportions."
"Our hearts are shattered," Trump said in a press briefing at the White House, after holding a moment of silence. "Our prayers are with you now and in the days to come."
"We are all searching for answers," Trump said, adding, "We do not know what led to this crash" but have "some pretty good ideas."
President Donald Trump's nominee for Army secretary, Daniel Driscoll, said at his Senate confirmation hearing Thursday, "I think we might need to look at where is an appropriate time to take training risk, and it may not be ... at an airport like Reagan."
While he does not have any insider details on the crash, Driscoll said, "It's an accident that seems to be preventable, from what we can tell today."
-ABC News’ Matt Seyler
Washington, D.C.'s Ronald Reagan Washington National Airport has reopened Thursday morning, about 14 hours after the devastating crash.
Planes are now arriving and departing.
Former President Joe Biden wrote on social media that he's "praying for the families of the victims who tragically lost their lives in the plane and helicopter crash."
"We are immensely grateful to the brave first responders and emergency personnel on the scene," he added.
Former President Barack Obama wrote on social media, "Our hearts break for the families who lost loved ones in the tragic plane and helicopter crash."
"Michelle and I send our prayers and condolences to everyone who is mourning today, and we’re grateful to the first responders who are doing everything they can to help under extremely difficult circumstances," Obama said.
