All 67 victims in last week’s deadly collision of an American Airlines regional jet with an Army Black Hawk helicopter over the Potomac River have been recovered, officials said Tuesday. Sixty-six of them have been identified, the D.C. Fire and EMS department said.

Rescue responders had been working over the past several days to remove wreckage from the plane, a Bombardier CRJ-700, lifting an engine, fuselage and other parts of the aircraft from the water.

American Airlines Flight 5342, operated by its regional subsidiary PSA Airlines, was seconds away from landing at Washington, D.C.’s Reagan National Airport Wednesday night when it collided with an Army helicopter, killing all 64 people on board the flight and three military crew on the Black Hawk. The helicopter was on a training mission, officials said.

It was the deadliest U.S. air crash since 2001 and the first deadly major passenger airline crash in the U.S. in nearly 16 years.

Investigators are still probing the cause of the collision. The National Transportation Safety Board, which is leading the investigation, said it has interviewed air traffic controllers on duty that night, including the person who was working at the time of the collision.

The American flight was flying at an altitude of about 300 feet at the time of the collision. Altitude has become a key question in the investigation. Helicopters in that area must fly at a maximum altitude of 200 feet, under Federal Aviation Administration rules. The NTSB has recovered the two data recorders from the American plane as well as the recorder from the Black Hawk.

The FAA on Friday prohibited helicopters from flying in the area near the airport indefinitely.

American Airlines CEO Robert Isom told employees in a note on Tuesday that the company would hold a moment of silence on Wednesday to mark a week since the crash.

“Caring for and supporting everyone affected by this tragedy remains our top priority,” said Isom, who traveled to Wichita, Kansas, where the flight originated, to visit with local employees and officials.

While air crashes are extremely rare, American said it operates a so-called CARE Team for such rare disasters.

The team is made up of about 2,000 employees who volunteer from across the airline. They are specially trained by the carrier’s emergency planning and response teams to help victims’ family members and provide information from the company. They also coordinate travel arrangements; arrange child, elder or pet care; assist with logistics like getting changes of clothing, toiletries and transportation; and listen to affected family members.

American’s COO David Seymour and other operations staff members were in Washington, D.C., this week to support that team, Isom said.

“Our CARE Team has stepped up in a significant way in the wake of this unimaginable tragedy, and I’m so proud of everything they are doing,” he wrote.