PHILADELPHIA (AP) A four-story building being demolished collapsed Wednesday on the edge of downtown, injuring 12 people and trapping two others, the fire commissioner said.

Rescue crews were trying to extricate the two people who were trapped, city Fire Commissioner Lloyd Ayers said. The dozen people who were injured were taken to hospitals with minor injuries, he said.

The collapse involved a building that once housed a first-floor sandwich shop. It collapsed, sending debris onto a Salvation Army corner thrift store next door. The two are adjacent to an adult bookstore and theater that had been taken down earlier.

Rescuers were using buckets and their bare hands to move bricks and rubble to search for survivors.

Witnesses said they heard a loud rumbling sound immediately before the collapse.

Veronica Haynes was on the fifth floor of an apartment building across the street.