An RAF Nimrod spotter plane today joined a search and rescue operation off the Essex coast as fears grew for a yacht destined for Harwich.

The 28-foot Tuila should have reached the harbour six days ago in a crossing from Holland that can take as little as 24 hours.

But the crew - skipper Adam Clackson in his 50s, and three Cambridge post-graduate students - has not been heard from in days.

Last night the Harwich lifeboat joined other crews in a search up to 20 miles off the coast. The boat returned to base when the search was called off for the night at 12.15am.

The Tuila was destined for Ipswich but would have had to sail through Harwich Haven. Today's search was extending along the Essex and Suffolk coastline and out across the North Sea.

A spokesman for Thames Coastguard at Walton today said no lifeboats would be sent out today unless the Nimrod and a Dutch Orion spotter plane found any fresh information.

He said: "The search has now widened to take in 9,500 square miles. Unless we get a better idea of where they are, there will be no lifeboats out today.

"At the moment it does not look encouraging. We can just hope they are making their way slowly across perhaps with a flat battery for their radio."

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