A 60-year-old man suffered life-threatening injuries after an explosion in a refrigeration unit at a Turlock grocery store.

The incident was reported shortly before 11:30 a.m. Friday at the Carniceria La Rancherita store at 1160 W. Main St.

The man had been working at the store for several days as an independent contractor servicing a refrigeration unit, said Turlock Police spokesperson Officer Mayra Lewis.

The explosion was in a unit outside the store attached to a side wall. It’s unknown at this time what caused the explosion.

The repairman sustained severe injuries to the upper left side of his body and lost a portion of his arm. He was rushed to a nearby hospital for treatment.

California’s Occupational Safety and Health Administration was called to the site to investigate the accident.