PORTLAND, Ore. -

Portland authorities found a marijuana grow operation in the basement of a house fire that displaced two people in southwest Portland on Thursday night.

The Oregonian reports fire crews discovered an electrical hazard related to lights used for growing about 50 plants, as well as a severed natural gas line.

A spokesman for Portland Fire & Rescue says Portland Police are investigating whether the marijuana plants were being grown legally.

The cause of the fire is also under investigation. Lt. Rich Chatman says it is unclear whether fireworks contributed to the blaze.

There were no injuries reported.