Investigators searching for wreckage from last week’s deadly midair collision between a US military Black Hawk helicopter and an American Airlines plane near Washington, DC, conducted an overnight scan of the Potomac River where the aircraft fell using advanced imaging technology to map the riverbed and locate debris.

Salvage crews have been working to recover the wreckage of the American Airlines jet and the Black Hawk helicopter.

Air traffic controllers asked Flight 5342 to switch runways when coming in to land. Black box recordings from the jet and the military helicopter it collided with will help reveal whether this contributed to the accident.

The National Transportation Safety Board has released an update on the status of its investigation into the midair collision that occurred on Jan. 29 near Ronald Reagan National Airport, revealing that all major pieces from both the airplane and the helicopter involved have now been recovered from the Potomac River.