WASHINGTON (AP) — A former Blackwater security guard testified Wednesday that he and two colleagues shot their weapons into a car in Nisoor Square in Baghdad, part of a barrage of gunfire that claimed the lives of a mother and her son and led to the shootings of 30 other Iraqis.

In a calm voice, Jeremy Ridgeway told a jury that what started as “just another day at the office” in Baghdad suddenly erupted in fire from automatic weapons aimed at a car moving toward the heavily armored convoy of Blackwater guards.