Three lifeguards were being hailed as heroes today after a dramatic life-saving rescue involving three dozen children and four adults.
The party of 40 were plunged into the cold waters at Tenby, west Wales, after a raised sandbank they were on collapsed into the sea yesterday.
RNLI lifeguards Adam Pitman, Jon Johnson and Coral Lewis were patrolling Tenby South Beach and had already spotted the group before they got into trouble and went into immediate action.
Using nothing more than rescue boards and fluorescent buoyancy aids they ferried everyone to safety.
They then performed first aid on a number of casualties saving lives with their rapid response and professional action, rescue chiefs said.
Dave Miller, Coastguard Sector Manager in South Pembrokeshire, said: "The three RNLI lifeguards did a superb job today.
"If not for their fast response times and the methods they used at the scene, lives would have been lost."
The rescue happened at 4pm at a sandbank known locally as the White Back at the right side of the beach outside the red and yellow flag zone.
At the time, the group of children and adults was making its way back to the shore after receiving a warning from one of the lifeguards.
An RNLI spokesman said: "The (group was) walking along the long sandbank which as the tide comes in liquefies and gets swept away.
"They found themselves in the sea becoming out of their depth in what are treacherous waters."
Two casualties were treated at the scene, one who was suffering an asthma attack and the other who had suspected secondary drowning.
The spokesman added: "As well as the RNLI lifeguards and Coastguard, the air ambulance paramedics and two land ambulance teams were also at the scene.
"Six of the group's lives would have been lost had the lifeguards not intervened."
All those rescued are understood to have recovered.
The children involved in the rescue were aged between 12 and 15, and were staying at the nearby Kiln Caravan Park.
The RNLI's Jon Johnson was on his way to warn the group of the potential danger when the sandbank shifted, plunging all 40 people into the water.
He told BBC News: "They were all fully clothed which made it a lot harder for them to swim and even some of them couldn't swim, so at this time I entered the water whilst calling for backup on the radio."
He went in on an extended surf board and performed a relay rescue with another lifeguard, taking about 10 minutes to clear the water.
"They didn't know how dangerous sandbanks could actually be. They were just going for a leisurely walk and seconds later they are in overhead waters, fully clothed.
"They were very panicky, they were very scared but fortunately the lifeguards were there in seconds and we just had to reassure them."
He said there were many warning signs on the beach and it was "very lucky" the lifeguards were on patrol.
Mr Pitman said the group had been very lucky that lifeguards were patrolling the area at the time that the sandbank shifted.
He told Sky News: "That sandbank is the major hazard on the beach.
"They were very lucky that we just happened to be patrolling that area of the beach at that time, we were just being pro-active having a patrol up there.
"As we are all local we probably have about 30 years' experience between all lifeguards so we were very well aware of that hazard and the dangers it can cause to the people walking on it."