A landscape gardener was killed when a trench he was digging for an ornamental lake collapsed.

Karl Achermann's workmates struggled to free him after he was buried up to his neck in mud.

Firefighters and paramedics were called in to help but Mr Achermann, 43, of Barnsden Farm, Duddleswell, near Crowborough, was pronounced dead.

Emergency teams worked late into yesterday evening to retrieve his body.

A police spokesman said: "It is not yet clear what happened but this appears to have been a terrible accident."

The gardeners were working in the grounds of Greenbanks, a luxury detached house in Shepherd's Hill, Buxted, near Uckfield, which are being landscaped.

It is understood the trench was not fully supported when the accident happened just after 2.50pm.

Mr Achermann was working in the 8ft-deep trench when one side gave way.

Villager Martin Bruce, 38, said: "I saw the police helicopter land and wondered what was going on.

"Then I saw a hive of police, fire and ambulance activity and knew something terrible must have happened."

A fire brigade spokesman said: "The site had been dug using a JCB. It would appear the man had been working inside the trench when it suddenly collapsed. He was in about 6ft but the trench was deeper than that.

"He was pronounced dead at the scene."

Health and Safety Executive officers went to the site last night to begin an inquiry.

The tragedy comes as a report claims that 71 construction workers were killed in 2002-03, more than in any other industry.

A further 4,780 were seriously injured, more than three times the average for other key industries.

The number of deaths and injuries has been cut by five per cent since 2001.

But the National Audit Office (NAO) report said that was not enough.

The construction industry has set itself a target for cutting deaths and major injuries by 60 per cent by 2010.

The NAO, however, said it was unlikely to meet that target.

The Government's spending watchdog has drawn up a report on improving health and safety in the industry.

It said the industry and government organisations "could do more" to improve the health and safety of workers.

The report also called on the Health and Safety Executive to improve the way it assesses its own campaigns to improve safety.

Trench deaths are relatively rare.

In March 2001, 38-year-old Peter Thompson survived after the trench he was digging collapsed in St Helen's Road, Hastings.

Most of his body was covered by clay and soil in the deep but narrow trench.

He was freed after seven hours with chest and leg injuries.