A MAJOR investigation is under way today after two engineers died while working on a disused marine fuel tank on a Suffolk waterway.The bodies of the two men, both believed to have been married with children, were recovered at around 9.

A MAJOR investigation is under way today after two engineers died while working on a disused marine fuel tank on a Suffolk waterway.

The bodies of the two men, both believed to have been married with children, were recovered at around 9.30pm yesterday after a seven-hour operation involving firefighters, paramedics, police, coastguard and harbour workers.

They had been working in the five-metre diameter, 15-metre long tank for marine engineers Small and co at the shore of Lake Lothing, Lowestoft, when they became trapped.

Emergency services were called to the scene to gain access to the partly-submerged tanks, which contained little air for the men to breathe.

But after a dramatic seven-hour operation involving more than 30 firefighters from across Suffolk, it was revealed that the two men had died.

It is believed they were overcome by fumes.

Last night, a spokesman for Suffolk police said: "The Health and Safety Executive has been informed and will be investigating it as an industrial accident and we will be providing assistance. The coroner has also been informed."

The men, who were welders for the Lowestoft-based marine engineering company Small and Co, had been working inside one of four partly submerged tanks moored together off land owned by Associated British Ports (ABP) and across the water from dry docks belonging to their employer.

The alarm was raised shortly after 2pm when police were called by ambulance paramedics to a derelict quayside industrial site.

Although there were hopes the men were still alive, it later transpired that the would-be rescuers realised at an early stage that both men were dead.

As police guarded the perimeter and officials from Small and Co, ABP and Lowestoft Harbour came and went, local fire crews were joined at the scene by colleagues from Ipswich, Felixstowe, Bungay and Beccles.

As darkness fell, lights and torches flashed across the waters of the harbour as rescuers worked to gain access to the tanks, and soon after 9.20pm the bodies of both men were brought out of the container.

At one point it was suggested that there had been an explosion in the tank, believed to have last been used for fuel storage more than 20 years ago.

But Suffolk divisional fire officer Eddie Meelan said there was no evidence to support the claim. He said the operation had been difficult.

"There was fuel slurry in the bottom of the tank," he said.

"But there has been not explosion the we are aware of. They had entered into an oxygen deficient atmosphere and they had been overcome," he added.

"We were not aware of any oxygen monitoring equipment."

He said the men were already dead when fire crews arrived at the scene at School Road, off Victoria Road, Oulton Broad.

Mr Meads said that although some water had got into the tank there had not been any danger of it flooding. An arc welder was used to widen an opening in the tank so that the bodies could be retrieved, although that process was hampered by heavy steel girders built in to strengthen the tank

"We had to be very careful getting in with the breathing apparatus," he said.

He added that at the operation's peak there had been 30-35 firefighters on site, backed by a communications control vehicle, a unit to provide additional light, a turntable ladder and a coastguard's boat in the lake.

Engineers from Small and Co also helped in the release of the bodies.

Mr Meads said it was impossible to say whether either of the men had fallen into the tank, moored against derelict industrial land, sandwiched between Sanyo and Cosalt works sites.

"There were no witnesses although there had been other people nearby. There is Jacob's Ladder, a metal ladder, in the tank."

But he said that he was not aware that either man had been wearing a harness.

It was already dark by the time a heavy-duty crane was brought in to assist emergency service vehicles, including a turntable ladder and lighting unit from Ipswich, specialist rescue equipment from Felixstowe and a control and communications vehicle from Beccles.