SUN VALLEY ( —Los Angeles Fire Department crews Wednesday were responding to an apparent gas water heater explosion in the San Fernando Valley.

The incident took place around 11:15 a.m. at a yogurt shop that is under construction in the 8900 block of Glenoaks Boulevard, officials said.

READ MORE: School Bus Involved In Crash In Compton

A gas company employee and two workers from the shop were installing a tank-less water heater when it exploded.

One of the injured men ran into a nail salon next door to ask them to call 911.

READ MORE: Woman Shot, Critically Wounded By Long Beach School Security Officer Near Millikan High

“He had a lot of scarring. He lost hair. His whole face was on fire,” a woman from the salon said.

All three victims were transported to a local hospital with moderate burns to their face.

MORE NEWS: Student Fights Off Suspect In Violent Overnight Attack Near Chapman University Dorm: 'I Chased Him Back Up The Stairs, Cursing Him Out'

Officials were investigating how the water heater exploded.