A chunk of hillside in an upscale neighborhood where a landslide damaged homes last year gave way Thursday, further worrying residents and engineers.

It wasn't clear how much damage the new collapse caused to houses at the bottom of the slide, city spokesman Bill Harris said. There were no reports of injuries.

The unstable piece of land slid down 5 to 6 feet on Thursday, officials said.

San Diego has been rushing to stabilize the street of million-dollar homes in the La Jolla area since the initial collapse in October sent a 200-foot-long section of earth 20 feet downhill.

Six houses were uninhabitable after that collapse. Residents have blamed the city for not recognizing the threat after cracks appeared in the street above. Damage was an estimated $48 million.

Experts had said that the likelihood of a second similar collapse was low, but that smaller slides were possible as the earth settled.