Flames tore through the second floor of a Hopatcong home early Friday evening.

The cause of the fire has yet to be determined, Fire Marshal Rich Cook said.

Hopatcong firefighter Chris Mason injured his left ankle when the attic steps collapsed under him, Cook said. The Hopatcong ambulance squad transported Mason to St. Clare's Hospital in Dover for treatment, Cook said.

"Although not broken, the injury will require Mason to be off the ankle for some time," Cook said.

Click here for video from the fire.

A man inside the home was able to escape the 32 Rollins Trl. structure before emergency responders arrived, police said. The homeowner's name and the name of the man caught in the blaze have yet to be released.

More than five fire engines from the borough and Stanhope responded to the blaze, which began around 5:50 p.m. The home was quickly extinguished, police said.

"The fire department did a real good job putting out the fire," Cook said. There was a lot of black smoke."

The burned home was Hopatcong's second structure fire. In January, a stone Pickrel Point home burned through the early morning.

The fire closed much of Rollins Avenue throughout the early evening.

A "for sale" sign was on the property's front lawn.