Searches are continuing for the boss of one of the world's best-known surfer brands, who has gone missing at sea off the coast of southwest France.

Pierre Agnes is chief executive of Boardriders - which owns brands including Quiksilver, Roxy and DC Shoes.

He set sail yesterday morning in thick fog.

His boat was later found washed up on a beach at Hossegor, which is around 30 km north of the resort town of Biarritz.

In a statement quoted by US media, Boardriders said: "The Boardriders family and entire surfing world are devastated by this news.

"We are concentrating on working with the local authorities on the search and rescue effort and supporting Pierre's family."

In an Instagram post, professional surfer Kelly Slater said he was "praying for a miracle", adding that Mr Agnes has had a "profound effect" on his life.

The organisers of the World Surf League said their "thoughts and prayers are with his friends and family all at this time".

Deeply troubling news concerning Quiksilver CEO Pierre Agnes, who is currently missing off the South Western coast of France. Our thoughts and prayers are with his friends and family all at this time, as well as the search and rescue teams https://t.co/a2heC234Ce

— World Surf League (@wsl) January 30, 2018