Two construction workers were injured when a propane tank is believed to have exploded Thursday at a home that was being built in eastern El Paso County.

Construction crews said they arrived to the house in the 24000 block of East Highway 24, between Peyton and Calhan, to install drywall, but when they opened the garage door to set up equipment there was an explosion, the El Paso County Sheriff’s Office said.

Authorities believe the explosion was caused by a possible propane gas leak was ignited by an unknown spark.

“No arson or foul play is suspected,” the Sheriff’s Office said.

The construction workers injured in the blast were treated at an area hospital. The extent of their injuries is unknown.