Los Angeles, CA – Natural gas that seeped from one condominium into another caused an explosion in a two-story building in West Los Angeles, slightly injuring a man, authorities said today.

The blast happened around 10:10 p.m. Monday in a condominium in an 18- unit building at 1535 S. Granville Ave., said Brian Humphrey of the Los Angeles Fire Department.

Two men in a second-story unit had just finished cooking when they noticed the smell of gas in their kitchen, he said.

They were unable to locate the source of the odor, and moments later, after one of them had left the room, a “thunderous but fire-free explosion occurred behind the stove, fully toppling the appliance as well as a refrigerator nearby, and causing significant damage to walls within the kitchen and adjacent room,” Humphrey said.

The man who was standing near the stove suffered a lacerated leg while the other was uninjured, he said. Both declined to be transported to a hospital.

Firefighters determined the leak came from a gas-fed fireplace in the unit below, Humphrey said. The gas collected in the upstairs wall space and was somehow ignited, he said.

A Southern California Gas Company representative determined the hazard had been abated, and a city Department of Building and Safety inspector deemed the affected condominium and the rest of the building safe for occupancy, Humphrey said.

A damage estimate was not immediately available.