Firefighters and teachers rescue elderly residents from burning San Francisco building

SAN FRANCISCO, Calif. - San Francisco firefighters responded to a 2-alarm fire on Friday, where seven people were injured and 18 people were displaced. 

The fire department said that two of those injuries were critical and two were serious.

The fire broke out at the St. Francis Square Co-op where many of the residents are senior citizens.

"I heard the fires, and I saw flames coming out of all the windows," said resident Nan Park.

Crews from the Red Cross were also on the scene to assist the 18 people who were displaced, according to fire officials. 

The fire was reported about 10:30 a.m. on 10 Inca Lane and was contained about an hour later, fire crews said. 

Two teachers at nearby Rosa Parks Elementary School, Vincent Reyes and Cecily Ina-Lee, rushed over to help.

"It was scary to see senior stuck up on balconies," Ina-Lee said.

They don't see themselves as heroes.

"We're teachers, so we care about other people," Reyes said. "And I think, hopefully anybody would do the same thing."

The San Francisco fire department originally reported that the fire was in an assistant living facility on 1355 Ellis Street. 

In a video released by the fire department, all three floors of the residential complex were engulfed in flames.

"Very fast-moving fire, and it's rare for a fire during the day to make that much headway before we arrive," said Deputy Fire Chief Bob Postel.

"Crews immediately pulled two people out of the top floor in the rear, two people out of the ground floor in the rear who was trapped, one person on the second floor in the rear," Postel said.

The cause of the fire is still under investigation.