Investigators have recovered the flight recorders—also known as black boxes—from both the commercial jet and the military helicopter involved in the mid-air collision near Reagan National Airport in Washington,

The black boxes of the American Airlines plane submerged in the Potomac River from Wednesday’s crash with a military helicopter have been recovered, the National Transportation Safety Board said late Thursday.

Investigators have already recovered the cockpit voice recorder and flight data recorder of the American Airlines plane that collided with an Army helicopter as the plane was landing Wednesday night at Ronald Reagan National Airport next to Washington,