Pueblo police are investigating an explosion involving hash oil.It happened Tuesday at a home on Grissom Street on the city’s east side.

People living in the home drove themselves to the hospital and were treated for second-degree burns to their face and arms.

A news release says the homeowners were attempting to make marijuana concentrate through hash oil extraction methods. During the process, the home filled with gas and was unknowingly ignited.

The homeowners face felony charges.