Boulogne-sur-Mer, northern France Getty images

A 13-year-old British boy is feared dead after being swept out to sea in northern France.

It is believed the boy was in water off a beach in Boulogne-sur-Mer with two younger brothers when he got into difficulty.

A search for him was launched at around 6pm local time on Monday, and continued late into the night.
The head of Boulogne lifeboat station said that the boy had been in a fast-flowing channel swimmers were not supposed to use.

"At this time of the year, for somebody in tip-top condition, the temperature of the water indicates a maximum survival time of about two to two-and-a-half hours," Gerard Barron said, as quoted by the Press Association.

He said the search had been resumed Tuesday morning, but the boy was not expected to be found alive. "The search is now being done by the police and the fire brigade. It is now a judicial inquiry," he added.

The boy's parents and two other people were taken to hospital with shock, AFP reported.