Lyanne Melendez/ABC 7

A rockslide crushed a car in Telegraph Hill on Jan. 23, 2012

Boulders came tumbling down a rain-soaked Telegraph Hill in San Francisco Monday morning, crushing a car and causing the partial evacuation of an apartment building.

The rockslide was reported at 9:37 a.m. near Montgomery and Lombard streets. The building affected is the Parc Telegraph apartments at 220 and 240 Lombard St.

Rocks landed on a parked car, but no injuries were reported. The car belongs to a security guard at the building, fire Battalion Chief Ed Gonzalez said.

Dawn Walker, who lives on the sixth floor of the building, said she wasn't sure what happened at first.

"I didn't know it was a rock, I thought it was an earthquake," Walker said.

Mohammed Nuru, interim director of the San Francisco Department of Public Works, said at the scene Monday morning that a geotechnical engineer and a geologist are being brought in to assess the rockslide.

"It's one of the largest slides I've seen," Nuru said.

A previous slide in 2007 affected the other side of Telegraph Hill, near Broadway and Vallejo Street.

There is no estimate yet for when the rocks will be cleared, but the residents of six units whose apartments back up to the hillside are being kept out of their homes for now as a precaution, he said.

Crews will be putting up a concrete barrier to stop some of the loose debris from shifting further, Nuru said.