Firefighters responded to the house in the Maplewood neighborhood of Bethesda around 4.30 p.m on Sept 10. Investigators are still working to find the reasons behind the Bethesda house fire that occurred earlier this month. This house fire has killed a man.

Investigators found Tunnels, Chemicals and wiring in the basement of that house. “The conditions in the basement became more and more unusual as the investigation went on,” Montgomery County Fire Chief Dan Ogren said Tuesday.

Investigators said as they reached the scene they could see smoke coming out from three levels of the house, and also all the conditions created a challenge in fighting the fire. Ogren said they discovered tunnels underneath the home the following day.

The tunnels and excavation did not hinder the fight against the fire, but an ignited gas line certainly did. The investigators also found equipment and chemicals that could be misused in the basement of the house.

By A.s