3-alarm fire in South Philadelphia probed as possible arson

A three-alarm fire in South Philadelphia was being investigated as possible arson Sunday, as a witness reported seeing two men near the scene and hearing an explosion just before flames erupted.

Emergency personnel responded to a report of fire inside an unoccupied property along the 2000 block of South Juniper Street, near Snyder Avenue, about 3 a.m., police said.

The blaze was quickly called to three alarms, and officers evacuated the area due to heavy smoke and power outages. About 17 people, including two children, were initially displaced from neighboring homes, according to the Red Cross.

Firefighters were able to wrest the flames under control shortly before 6 a.m. The property was under construction at the time, and no injuries were reported.

A witness told investigators he heard glass break and saw a man go inside the property about 20 minutes before the fire started, police said. The witness saw a second man standing on the building's roof, he said.

The first man exited, running south on Juniper, then east on Snyder, and about a minute later, the witness heard an explosion, he told investigators.

The witness was not sure what happened to the man he saw on the roof, police said.

The Fire Marshal deemed the blaze suspicious Sunday, but an official ruling on its cause was not expected to be issued until Monday, police said. An investigation remained ongoing.

Police described the men seen near the scene as a slim male, about 5 feet 8, wearing a black hooded sweatshirt, and a 5-foot-4, 150-pound Hispanic man with bushy curly hair and a goatee, last seen wearing a black hooded sweatshirt and jeans.

Anyone with information was asked to contact Philadelphia police.

Here are more photos of the scene, shared on social media: