Three people were killed after a bluff along a beach in Encinitas, Calif., collapsed Friday afternoon.

A woman died at the scene, and two people succumbed to their injuries at a hospital, authorities said. Two other people were injured.

Rescue dogs searched through the area of Grandview Beach, popular among surfers and families, after a 30-foot-long chunk of sandstone slid onto the sand below about 3 p.m.

“They were facing the ocean,” said Encinitas Marine Safety Capt. Larry Giles. “So, it came from behind them and basically overtook them and crushed them.”

Jim Pepperdine, who lives near the beach, told the San Diego Union-Tribune that he went outside to see what was happening after hearing the sirens.

“I saw first responders, and I saw lifeguards frantically digging people out of the debris,” Pepperdine said.

Jackie Benedict described the scene to NBC 7. “It was horrible,” she said. “I can’t imagine being at the beach and your life changing in the blink of an eye.”

Rescue workers arrived at the scene about four minutes after a lifeguard heard the collapse, officials said, adding that homes near the collapse, which sit above the bluffs, were not in any danger.

Paul Brencick, a spokesman for the city, said rescuers “worked tirelessly” to finish search efforts as the rising tide started coming in that evening.

Encinitas Mayor Catherine Blakespear said in a statement: “We are devastated by the tragedy today and our hearts go out to the victims and their families. We stand ready to help in any way possible. Our engineers and the public safety team are diligently working to assess bluff conditions.”

Much of the California coastline erodes naturally, and authorities have tried to warn people who use the beach of the risk. Brencick said there were multiple signs posted at the beach, and at many other California beaches, warning individuals to stay back from the bluffs.

The type of collapse that took place on Friday, as the tide was low, is less frequent than a collapse when the waves are high and touching the bluffs, Giles said.

Officials were working to reopen the beach Saturday after having an engineer check the bluffs for a potential second collapse.