Holland, MI – Investigators have determined a natural gas leak was the cause of an explosion that seriously injured a woman and her granddaughter at an apartment complex in Holland in November.

Capt. Mark Bennett with the Ottawa County Sheriff’s Office, which investigated the fire, said the explosion was the result of the build-up of natural gas in one of the complex’s units.

The Nov. 4, 2015, explosion sparked a massive fire that destroyed multiple housing units in one building.

The explosion occurred in unit 2, a two-story in the Pompa Vidals complex at 80 E. Lakewood Blvd., and blew out the unit’s walls and knocked pictures off the walls of neighboring apartments. The fire quickly engulfed unit 2 and spread to the two adjacent units.

Maria Gutierrez-Fuentes, 60, escaped the flames with her granddaughter, 2-year-old Layla Cahue-Romero. Both suffered serious injuries from the flames.

Layla was released from the hospital within days of the blaze. The current condition of the two females was not available as of press time.

Soon after the fire, Holland Charter Township Fire Chief Jim Kohsel said the water heater in unit 2 was reportedly under some maintenance prior to the explosion, and the townhouse complex owner, Ceferino Pompa, told The Sentinel he was called to unit 2 that morning after a resident notified him there was water in the basement, where the water heater is housed.

Pompa said he saw the water heater, which is heated by natural gas, was leaking water and that he shut off both the water and gas to the water heater at about 9:45 a.m., about two hours before the explosion.

He said he did not smell any natural gas at that time.

Bennett said during the maintenance, a gas line began leaking natural gas.

“It wasn’t capped off so that area filled with natural gas and then, through an unknown ignition source, ignited,” he said.

Bennett said the incident was accidental and there was no suspicion of any criminal behavior.