Massive fire engulfs senior living facility outside of Philadelphia The fire burned much of the structure to the ground late Thursday.

 -- A massive fire engulfed a senior living facility west of Philadelphia on Thursday night, sending emergency responders scrambling to remove patients from the large complex.

At least 20 people have been injured in the fire, according to Chester County Emergency Services.

The mayor of West Chester said there were a few residents who were unaccounted for, saying Friday afternoon they were "hoping for the best." The Bureau of Alcohol, Tobacco, Firearms and Explosives, which was on the scene investigating the fire, said no family members had reported anyone missing.

The five-alarm fire in West Chester, Chester County began just before 11 p.m. at Barclay Friends Senior Living Community and burned for hours before being brought under control early Friday.

Dozens of residents could be seen being wheeled out on beds and in wheelchairs.

Chester County Hospital said it had admitted nine patients, including one paramedic. The hospital said they were suffering from smoke inhalation and minor leg injuries. Paoli Memorial Hospital has received seven patients, none critical, all for smoke inhalation, it said.

Authorities said Friday the structure was still too unstable to enter and make sure everyone escaped.

West Chester is about an hour west of Philadelphia.