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.

A plane equipped with lasers is helping search for debris from the deadly collision of a passenger jet and Army helicopter near Washington.

Investigators trying to figure out what led to the deadly midair collision between a US military Black Hawk helicopter and an American Airlines plane near Washington, DC, last week will brief lawmakers Thursday on what they’ve learned after combing through data from both aircraft and air traffic control.

The U.S. Army Corps of Engineers says crews have successfully taken all major pieces of wreckage from the D.C. plane crash out of the Potomac River. The announcement came Thursday evening, just a day after the remains of all 67 victims killed in the midair collision were recovered and positively identified,