One person remains unaccounted for after a massive fire broke out inside a building in Pittsburgh’s Sheraden neighborhood early Saturday morning.Pittsburgh police and fire responded to a 2-alarm structure fire in the 700 block of Hillsboro Street just after midnight. WATCH PREVIOUS VIDEO IN PLAYFINDER ABOVE Officials said when they arrived on the scene, flames were seen coming from the second floor of the building. As firefighters worked to contain the fire, they said the building partially collapsed, causing the roof and third floor to fall onto the second floor of the structure. A man was believed to be inside the building at the time of the fire. Police said he remains unaccounted for. Police utilized drones to assist in the search and rescue, but were unable to locate anyone inside as of 11 a.m. Saturday. The Department of Permits, Licenses, and Inspections has been notified and will develop a demolition plan, as well as assist with possible recovery efforts.Firefighters said they established a fire watch at the scene and extinguished two flare-ups, one that occurred at 4:45 a.m. and another at 7:20 a.m. Police will remain on the scene until the building is demolished.The cause of the fire is under investigation. Download the WTAE app to stay connected with breaking news. Sign up for our email newsletters to get breaking news in your inbox.

PITTSBURGH —

One person remains unaccounted for after a massive fire broke out inside a building in Pittsburgh’s Sheraden neighborhood early Saturday morning.

Pittsburgh police and fire responded to a 2-alarm structure fire in the 700 block of Hillsboro Street just after midnight.

WATCH PREVIOUS VIDEO IN PLAYFINDER ABOVE

Officials said when they arrived on the scene, flames were seen coming from the second floor of the building. As firefighters worked to contain the fire, they said the building partially collapsed, causing the roof and third floor to fall onto the second floor of the structure.

A man was believed to be inside the building at the time of the fire. Police said he remains unaccounted for.

Police utilized drones to assist in the search and rescue, but were unable to locate anyone inside as of 11 a.m. Saturday.

The Department of Permits, Licenses, and Inspections has been notified and will develop a demolition plan, as well as assist with possible recovery efforts.

Firefighters said they established a fire watch at the scene and extinguished two flare-ups, one that occurred at 4:45 a.m. and another at 7:20 a.m.

Police will remain on the scene until the building is demolished.

The cause of the fire is under investigation.

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