Four teenagers trapped on rocks by the rising tide were carried to safety by the lifeboat.

Dramatic footage shows crews from Littlestone RNLI arrive just in time to rescue the youngsters - two boys and two girls - after the rocky groyne they were standing on quickly submerged under the sea.

The rescue took place at the beach near Folkestone's Lower Leas Coastal Park, half a mile west of the Harbour Arm, yesterday afternoon.

Crews arrive to help rescue the stranded teenagers. Credit: FolkestoneFollow on Instagram

Crews received the call at 1.50pm and interrupted their part in a display at Dungeness and Rye Harbour RNLI's open day to assist in the rescue.

Taking the lifeboat in as close a possible to the fast disappearing rocks, the crew helped the teenagers aboard the lifeboat two at a time before returning them to shore safely.

Video of the rescue was captured by the Instagram account FolkestoneFollow, who was full of praise for the work carried out by the RNLI crews.

A small crowd also gathered along The Leas to watch the crews during their efforts.

Littlestone Lifeboat Helm Simon Matthews said: "You have to expect the unexpected as lifeboat crew, one minute you’re flying past crowds of cheering onlookers displaying the boat and the next you are saving the lives of youngsters from the dangers of rocky groynes."

The boat returned to the station and was made ready for service by 3.30pm.

Crews have now issued a warning about getting stuck on rocks, and have listed advice on how to avoid it.

This includes checking tide times, being aware of surroundings and the tide's direction.

A safety warning advised: "A beach can seem like a vast playground but the tide can come in surprisingly quickly. As the tide moves up and down the beach, the depth of the water changes throughout the day, sometimes by as much as 10 metres.

"As the tide comes in, simply walking further up the beach and away to safety might not be an option.

"If you've walked round to another cove at low tide, or walked around an outcrop of rocks, the water can soon block your way back as the tide turns. If the cove you're in doesn't have steps or access of its own, you could be in trouble."

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