British police say they are not investigating an explosion that left two dead on Sunday as a terror incident, after officials raised the U.K.'s terrorism threat level.

Six people were injured in an explosion outside a Pearland mobile home when high-octane fuel was added to a fire. Investigations are ongoing, officials say.

The house on 130th Street exploded in a roar of flames just before 3 a.m. Thursday and collapsed. It's set to be fully demolished on Friday.