Investigators are trying to determine the cause of an explosion and fire at a home in southeast London Monday that sent one man to hospital in serious condition.

Police say the victim sustained second-degree burns to his hands, face and back after being taken from the home at 1335 Hamilton Rd., west of Clarke Road.

Three others who were in the home, which contains rental units, escaped injury.

The blast happened at around 4 p.m. and reports said it could be heard more than one kilometre away. It caused the west wall of the home to buckle and knocked bricks and siding off the front of the home.

House explosion 2

The explosion knocked bricks off a large chunk of the front of the house at 1335 Hamilton Rd. (Gary Ennett/CBC News)

Police say the owner of the building was away at the time of the explosion.

Investigators from the Office of the Fire Marshall and Emergency Management, as well representatives of the Technical Standards and Safety Authority, were on the scene Tuesday trying to determine what led to the blast. 

London's acting deputy fire chief Jack Burt told CBC News investigators will examine the structural integrity of the building.