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 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,

Recovery operations are underway after an American Airlines flight and an Army helicopter collided and crashed into the Potomac River near Ronald Reagan Washington National Airport on Wednesday night.