MOUNT VERNON, Wash. - A 100-year-old church building in Mount Vernon was destroyed after a three-alarm fire broke out Tuesday night.

Investigators say an electrical short may have sparked the blaze at the Christian church, called Roca Fuerte, or "Strong Rock." They've ruled out arson.

Sixty people were inside for Bible study when the lights went out and smoke started to fill the building around 9 p.m. Everyone got out safely and no one was injured.

By the time firefighters arrived, the entire inside of the church was engulfed by flames. The fire department says flames spread quickly through the three-story wood-frame building and the roof collapsed.

Two nearby homes were damaged by smoke and water. Firefighters tried to contained the flames and ambers from traveling outside the damage zone.

By Wednesday morning, firefighters were still mopping up flames.

Pastor Jose Nolazco and his wife surveyed the damage on Wednesday morning.

"Everybody was, yesterday, sad and crying," said Marisela Nolazco.

The church, which had occupied the building for about a year, was a complete loss. The fire department estimates the loss at $750,000.

"It's really sad," said Natalie Cisneros, a Mount Vernon resident. "Because it's an old building. It's been here forever. And when we're losing all our buildings it's just real sad."

The congregation of Roca Fuerte said they will rebuild.