YOKOHAMA -- One man fell unconscious and another was slightly injured Aug. 11 when an explosion ripped through a garbage disposal facility in Kanagawa Prefecture.

Police and firefighters are investigating the cause of the explosion, which occurred around 7 a.m. near a chemical storage area in the basement of a six-story municipal garbage disposal facility in Chigasaki, Kanagawa Prefecture.

Kazuaki Hirota, 31, an employee who was working on the ground floor lost consciousness after inhaling gases released by the explosion, police said. He remains in serious condition.

Kuniyo Sekiya, 51, who was waiting outside the facility in a car, suffered slight injuries to his hand when rubble from a wall that was destroyed in the blast broke through the windshield.

The explosion completely destroyed the basement and ground floors.

Five people had been monitoring the incinerator throughout the night. Two of them were working on the ground floor near the chemical storage area when the explosion occurred, police said.