U.S. authorities restricted helicopter flights near Reagan Washington National Airport on Friday, after a midair collision between an American Airlines passenger jet and a military helicopter killed 67 people this week.

Sixty-four people aboard a commercial airliner died Wednesday after it collided with a military helicopter midair near Reagan Washington National Airport. Both the American Eagle jet and Army Black Hawk are in the Potomac River.

While authorities focus on the cause of the US's deadliest aviation disaster since 2001, families are mourning their loved ones. Here's the latest.