Portland firefighters used an air bag to spread walls to free an Oregon woman who fell part of the way down a 20-foot wall and got herself stuck between two buildings.

The woman spent about four hours in a space 8 to 10 inches wide Wednesday morning. In addition to the air bag, rescuers also cut a hole and used a soapy substance to lubricate the concrete block walls.

After the woman emerged at 7:30 a.m., she raised her face, clenched her fists and shouted, "Oh, my God."

Witnesses told TV stations she had been seen smoking or walking on the roof of a two-story building before she fell.

Authorities didn't immediately name the woman.

• Portland