Paseo del Mar in San Pedro slid into the ocean Sunday afternoon, Nov. 20, 2011. A section of the cliff with a beach access road also appeared to have fallen. (Chuck Bennett/Staff Photographer)
A steady rain all day Sunday proved to be the tipping point for San Pedro's unfolding landslide along a section of Paseo del Mar on the town's ocean cliffs.

At about 3 p.m. in the afternoon, power lines and a palm tree began to sway. When authorities got close enough to inspect the road, a substantial new chunk of the road had completely collapsed, leaving a gaping, deep hole and part of the cliff and road in the ocean.

A section of the cliff where a beach access road also had begun crumbling also appeared to be sheared off as steady rains pelted the area all day Sunday.

No one was injured, but that was just "luck," said Los Angeles City Attorney Carmen Trutanich.

"It's bad. We're lucky no one got hurt," Trutanich said.

Trutanich was on his way to speak at a chamber of commerce meeting on the Palos Verdes Peninsula when he received a call from a constituent about the new collapse.

"I thought I've got to come here," he said. After he was given an escorted tour through the area, he said, "I was surprised to see the gaping hole in the road."

The muddy street had completely given way in the middle of the 900-foot-long section of the road between Weymouth and Western avenues.

The street had begun to buckle in the summer and was closed by mid-September. Ever since, the community has been put on landslide watch as cracks and fissures opened wider and deeper by the day.

Most recently, city engineers said the land was moving -- both vertically and horizontally -- at a rate of 4 inches per day, heaving itself toward the edge of the cliff and the ocean below.

Some wondered whether more of the street would collapse by daybreak. Trutanich said it didn't look like the landslide was over after his late afternoon tour.

While on the scene, Trutanich called the Los Angeles Police Department to make sure patrols would be watching for trespassers overnight. Authorities continue to stress that the area is extremely dangerous.

"Because this is such a new thing, there are going to be a lot of looky-loos out here," he told a worker at the scene.

Throughout the afternoon, spectators came to the area, braving the rains in hooded jackets and carrying umbrellas.

"Amazing, isn't it?" one man said as he and his wife peered through an 8-foot-tall chain link fence that keeps the public out of the danger zone.

"Wow, this is so weird," said another neighbor.

Several said some of the heavy equipment should be moved off the road. No equipment appeared to be damaged.

Workers are rerouting storm drain lines during the week to prevent more damage as the slide worsens.

A friend who witnessed Sunday's street collapse told Sally Simpson, who lives near the site, that she saw power poles begin to sway and heard a "snapping" noise.

Workers below on the beach told som