A businessman watched in horror as his luxury yacht burst into flames and sank just minutes into a trip out to sea.

Mike Knowles, of Britannia Court, Brighton, was with five friends on his £400,000 cruiser, the Cloudbreak, yesterday afternoon when it caught fire off the coast of Shoreham.

The group were taking the 58ft Sea Princess out for a spin for the first time since October after an expensive refit of the vessel during the winter.

But they were forced to abandon ship at 1.20pm when fire broke out on board just moments after it had pulled out of its mooring in Brighton Marina.

Fellow sailors helped them onto their vessels before lifeboat crews from Brighton and Shoreham took them back to the shore.

A plume of smoke at least a thousand feet high could be seen from Brighton and Hove, although the blaze was at least ten miles away just outside Shoreham Harbour.

The vessel burned for two hours as RNLI and coastguard crews had to stand by and watch because it was too dangerous to approach. It sank at 3.18pm.

The Maritime & Coastguard Agency has launched an investigation into the cause of the fire.

Did you film the fire? Contact The Argus on 01273 544511 or email us at news@theargus.co.uk.

To see pictures of the fire sent in by readers, click here.