COASTGUARDS warned a group of children about the dangers of tombstoning' in Portland Harbour.

A concerned member of the public raised the alarm after witnessing the youngsters jump off the Mulberry Harbours yesterday afternoon.

A team was dispatched to the area and gave the children safety advice when they returned to shore.

A Portland Coastguard spokesman said it was common for local children to swim out from Castletown and climb the ladders of the Mulberry Harbours in order to jump off. They are artificial piers developed during the Second World War to offload cargo for the D-Day invasion of France in 1944.

The spokesman said: "Jumping from the harbours is a very hazardous activity and could result in serious injury. There are all sorts of dangers in the harbour and we can only hope these children got the message."

Elsewhere, a lifeboat crew helped three people in a speedboat which became snagged on a fishing pot line off Old Harry Rocks. It was escorted back to port by another vessel.