Coastguards are warning youngsters to take care in or near the sea now that school summer holidays have started.

Recent warm weather has been a magnet for children to head to the beach to cool off in the water but this has led to problems for some, said Pete Overton of Thanet Coastguards.

The warnings come after coastguards were called to two emergencies in less than an hour. In the first, two teenagers were in danger of being swept out to sea on a surfboard off Joss Bay before being recovered by the team. The second call was to two young swimmers drifting off Nayland Rock in Margate. They were eventually rescued by the Margate beach lifeguards.

Pete said: “The advice has to be don’t go swimming at places where there are no lifeguards. It’s easy to be caught out by tides and you can be quickly in trouble if you aren’t careful.”

Another waterside activity which is fraught with danger is tombstoning - or jumping straight off the side of a pier or jetty into the sea. Youngsters have been leaping off the ends of Margate harbour arm and Broadstairs jetty.

“This is extremely dangerous,” said Pete, “because you just don’t know how deep the water is or if there are any rocks below the surface. Potentially, someone could be seriously hurt or even killed doing this.”