A large training exercise for Joint Base Lewis-McChord soldiers in Southern California came to a halt Saturday morning when an infantryman shot an Army Apache helicopter with live rounds.

No one was hurt in the incident, but the infantryman’s bullets punctured the JBLM-based helicopter four times and prompted a suspension of the exercise at the National Training Center in the Mojave Desert, said Ken Drylie, a spokesman for the training center.

It’s not clear why the soldier had live rounds in his rifle. Soldiers are issued blanks when they arrive at the training center to use in war games. They shoot at each other with blanks and a sort of laser tag during mock battles.

“The big question is how did it happen, which is why when it happened they immediately stopped training, and they did a 100 percent inspection to ensure there were no further live rounds where they shouldn’t be,” Drylie said.

Rifles at Fort Irwin are equipped with devices called blank firing adapters that allow the weapons to shoot as if they have live rounds. In this case, a live round blasted the adapter off the rifle and then subsequent bullets hit the helicopter.

Drylie said the soldier has not been disciplined. The Army conducted a preliminary investigation and determined the shooting was an accident.

“It’s a really weird accident, but it’s an accident,” he said.

The infantryman who shot at the helicopter serves in JBLM’s 1st Battalion, 17th Infantry Regiment. He was temporarily attached to a unit at the training center that acts as the enemy force when infantry brigades from around the country visit the post for large-scale exercises.