Three people have been killed and at least two others injured after a cliff collapsed just feet away from a lifeguard tower in California on Friday, authorities have said.

The tragic incident occurred around 2:55pm local time on Grandview Beach in Encinitas, just north of San Diego.

First responders, including lifeguards, raced towards the wreck and began digging victims out from beneath the rubble.

A female victim, who has not yet been named, was pronounced dead at the scene. Two other victims were airlifted to hospital in a critical condition but later died, officials revealed early Saturday morning.

One other victim was transported to hospital in an ambulance to be treated for a series of minor injuries.

'It has now been confirmed that two of the three victims that were transported to local area hospitals earlier today have succumbed to their injuries,' a statement from the city read.

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Three killed and two others injured after a cliff collapsed just feet away from a lifeguard tower in California on Friday, authorities have said (pictured: first responders attend to a victim)

The tragic incident occurred around 2:55pm local time on Grandview Beach in Encinitas, just north of San Diego

First responders, including lifeguards, raced towards the wreck and began digging victims out from beneath the rubble. The female victim, who has not yet been named, was pronounced dead at the scene and another victim was airlifted to hospital in a critical condition

A fifth person was treated for injuries at the scene but declined further medical aid when asked by paramedics.

At least two of the four victims were still trapped beneath the debris when first responders arrived, San Diego County Sheriff’s Lt. Ted Greenawald revealed.

According to the lieutenant a 30-foot-by-25-foot section of rock separated from the cliffside and crashed to the beach below.

Officials have said the cliff was unstable and the area was cordoned off to keep the public out of harm’s way.

A spokesperson for the Encinitas Lifeguards described the debris as being ‘extremely dense and heavy’ to NBC7, with crews needed heavy machinery to clear the scene.

Cadaver dogs were deployed at the scene to look for addition potential victims but the search yielded no further fatalities or injured persons before high tide.

At least two of the four victims were still trapped beneath the debris when first responders arrived, San Diego County Sheriff’s Lt. Ted Greenawald revealed

Cadaver dogs were deployed at the scene to look for addition potential victims but the search yielded no further fatalities or injured persons before high tide

For safety reasons city officials have closed the beach from Ponto Beach in Carlsbad to the area south of Grandview Beach.

‘It was horrible. I can’t imagine being at the beach and your life changing in the blink of an eye,’ witness Jackie Benedict told NBC.

Benedict said she watched on in shock as a group of people began digging around the debris to rescue the victims.

‘It’s just sad. I imagine what my family would be going through, and it brings you to tears. You don’t – just sitting there watching, knowing you’re helpless, you know, while someone’s trapped under there is gut-wrenching.’

A wooden staircase sits on the cliffs providing access to the beach from the street above; it was not impacted in the collapse

A spokesperson for the Encinitas Lifeguards described the debris as being ‘extremely dense and heavy’ to NBC7, with crews needed heavy machinery to clear the scene

There are also numerous homes atop the bluffs, but no damage or threats to the homes were reported

A wooden staircase sits on the cliffs providing access to the beach from the street above; it was not impacted in the collapse.

There are also numerous homes atop the bluffs, but no damage or threats to the homes were reported.

‘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,’ Encinitas Mayor Catherine Blakespear said Friday. ‘Our engineers and the public safety team are diligently working to assess bluff conditions.’

Encinitas resident Rebecca Kowalczyk, 30, died near the same area January 16, 2000, when a 110-yard-wide chunk of bluff fell on top of her and buried her. Kowalczyk was on the Leucadia beach watching her husband surf when she was killed, the LA Times reported.

A skip loader was brought in to move the dense, heavy debris. No other victims were found by late Friday night

Search and rescue personnel head down to the site of a cliff collapse at a popular beach Friday

Long stretches of beach in Encinitas are narrow strips of sand between stiff waves and towering rock walls

It’s currently unclear what caused Friday’s collapse. Experts say the most likely trigger would’ve been several years of wave action and rainfall causing the cliff to erode, dislodging rocks.

Jim Pepperdine, who lives on Neptune Avenue just south of the Grandview Stairs, went to take a look outside as he was concerned about sirens he heard in the area.

He told The San Diego Union-Tribune: 'I saw first responders, and I saw lifeguards frantically digging people out of the debris,' he said. He said it seemed like the victims were at the beach together.

'They were clearly distraught. It was a normal beach day gone awry.'

Encinitas Mayor Catherine Blakespear told CBS News: '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.'