A long crack is visible crossing Paseo del Mar and into the White Point Nature Preserve in San Pedro. Signs are up warning of a landslide potential. (Chuck Bennett / Staff Photographer)

As work crews continued to investigate a sinkhole beneath Paseo del Mar in San Pedro, it appeared there would be no quick or easy fix in the cliffside neighborhood known for land movement.

Engineers this week are busy making plans to relocate power poles - "in case something more drastic would occur," said Lawrence Cuaresma, district engineer with the city of Los Angeles Public Works Department.

Engineers at this point do not know what is causing the sinkhole, he said.

"I hate to speculate, we don't know if it's local or part of a wider, larger event."

Geotechnical experts from both Los Angeles city and county are assessing the area and will make recommendations, he said.

County Department of Beaches and Harbors reported finding additional cracks in the pedestrian walkway near the street south of the baseball diamond used by Mary Star of the Sea High School.

Access to part of the beach below was closed due to a "potential landslide."

Meanwhile, a 900-foot-long stretch of Paseo del Mar - between Weymouth Avenue to just east of Western Avenue - will remain closed indefinitely, he said.

The street was blocked on Sept. 19 after engineers determined that a sinkhole had developed beneath a bowl-like depression in the road that had been slowly developing since early July.

Using tape measures and instruments, surveyors determined that the hole beneath where the road buckled was 2 feet long and 3

feet wide. The hole appeared to be expanding.

Since then, crews have discovered cracks also in the land at the White Point Nature Preserve that is bordered by Paseo del Mar.

Sidewalks also have developed cracks on the south side of the roadway, and there has been some separation of the curb and the gutter, Cuaresma said. There also was some movement on an access road, now closed, that leads down the cliff to the beach.