Two workers have been pulled to safety after dangling from collapsed scaffolding outside a San Francisco building.

A fire department spokesman says one of the men was pulled by co-workers onto the roof of the building, while the other was rescued by firefighters. The men were dangling from their safety ropes between the 18th and 19th floors.

The spokesman didn't know what kind of work the men were doing on the scaffolding or why it collapsed.

Both of the men were transported to area hospitals.