BLUE SPRINGS, Mo. — A house explosion last week that left three people injured has been ruled accidental due to a gas leak.

The incident was reported just before 2 p.m. in the area of E. Pink Hill Road and NE Jellison Road on Friday, Sept. 15.

The Missouri Department of Public Safety tells FOX4 the explosion happened in the basement, in the area of a water heater.

The homeowner had been working on the installation of the water heater at least since Wednesday and had noticed the smell of gas.

The gas company was called and an employee was on scene when the explosion happened.

Neighbors tell FOX4 the couple who lives in the home are older, around retirement age.

The Central Jackson County Fire Protection District is helping with the investigation and the State Fire Marshal and OSHA are also assisting.

Three people are recovering with one of those victims said to have life-threatening injuries.