A fire in downtown Las Vegas has left at least six people dead and more than a dozen injured.

The blaze, considered the deadliest in the city’s history, broke out at the Alpine Motel Apartments, a three-story building, early Saturday morning, local KNTV reported. Residents of the building were seen jumping from second-floor windows to escape the inferno, Las Vegas Fire & Rescue told the station. Three pets were also found dead, according to KDWN.

The fire may have been accidental, fire department spokesman Tim Szymanski said.

The fire is believed to have been caused by a stove which may have been used to heat one of the apartments. Residents told rescuers that it was common as the building lacks heat.

Damage from the blaze is estimated to be around $500,000.