A Saturday night building fire in Lewiston is being treated as an active crime scene.

Firefighters say they arrived on the scene at 146 Grove Street to find a two-story, single-family, wood-frame residence with heavy fire conditions on the first floor.

No injuries were reported, but one dog was found dead after the fire was extinguished.

The origin and cause of the fire are under investigation, and fire investigators will conduct follow-up investigative activities during the upcoming week.

The fire was reported at approximately 8:46 pm Saturday.

Earlier this month, 41-year-old Nicholas Coy was accused of vandalizing and starting a fire at the same house and was released on bail.

Lewiston firefighters also were sent to three fires Thursday alone.