STAMFORD - Fire investigators removed a 500-gallon propone tank Thursday at the Stamford home that exploded last week.

Authorities have determined that the blast at 305 Webbs Hill Road was caused by the gas, but they are unsure of the exact reason. They plan on conducting tests to see whether the tank is leaking, at which point they will be able to better assess the scenario.

Officials say all of the propane was removed from the tank before they pulled it from the ground with an excavator.

The probe is likely to take several months.

For extended Chopper 12 footage from above the wreckage, watch the clip to the left or click News 12 Extra on Optimum TV channel 612.