TUCSON, Ariz. — A wildfire in southern Arizona started when an off-duty U.S. Border Patrol agent shot at a target to reveal a baby’s gender.

The 2017 fire near Green Valley burned 73 square miles of state and federal land. The damage and firefighting costs topped $8 million.

A video released Monday by the U.S. Forest Service shows the target explode after being hit with gunfire, sending a blue substance into the air. The tall, dry grass immediately bursts into flames.

A figure blacked out on the video moves toward the flames after a few seconds but then backs up. A male voice twice shouts “Start packing up!”

Agent Dennis Dickey said he constructed the target with an explosive substance inside. He pleaded guilty in September to a misdemeanor charge.