2 workers injured in explosion at Carmel High School in Indiana

CARMEL, Ind. -- An explosion during maintenance on a heater at an Indiana high school has injured a school employee and a contractor.

Carmel Fire Department spokesman Tim Griffin says Wednesday that the workers apparently were relighting the heater on the second floor of Carmel High School when it caused an explosion and fire.

The explosion is believed to have occurred about 6:30 p.m. A mechanical room and part of the roof were damaged.

The injured workers were taken to a hospital. Their conditions were not immediately available.

Griffin said some students were in the school when the explosion occurred. None were hurt and Wednesday evening school activities were canceled.

The school district said students were participating in various practices at the time of the explosion.

Carmel is just north of Indianapolis.