A spokesman says an explosion at a southern Indiana naval base's pyrotechnic facility sent four employees to the hospital.
Crane Army Ammunition Activity spokesman Tom Peske says the explosion happened about 5:40 p.m. Thursday during routine clean-up operations at Crane naval base about 85 miles southwest of Indianapolis. The four injured employees were examined and released from the hospital Thursday evening.
Peske says the blast occurred during a clean-up at the facility that produces illumination mortars the military uses to give light to soldiers. Peske says employees follow certain procedures to clean up any loose chemical dust at the beginning or end of a production run. He says he doesn't know what chemicals are used.
The facility has been shut down as Crane looks into the cause of the explosion.