A man was injured early Saturday when a building collapsed in the Kensington section of North Philadelphia.

Emergency crews were called shortly after 4:30 a.m. to the 2700 block of Emerald Street, near Sterner Street, for the complete "pancake" collapse of a three-story home, according to the Philadelphia Fire Department.

Firefighters smelled an odor of natural gas and requested Philadelphia Gas Works personnel respond to the scene, preliminary radio reports indicate.

One man was taken to Temple University Hospital with unspecified injuries, according to the fire department. The victim's age and condition were not immediately available.

The cause of the collapse remained under investigation Saturday.