Split bulkhead seen on video of wreck

Sea gives up its secrets as investigators locate last resting place of British carrier 'Derbyshire'

Both sections of the bulk carrier Derbyshire, which sank 16 years ago in the South China Sea, have been located by an expedition trying to discover why it sank.

The wreckage of the 90,000- ton ship - which was built on Teesside - lies 4,200 metres under the sea, 1,000 miles south-east of Japan. The main bow section was first discovered by an expedition funded by the International Transport Federation (ITF), a union-funded body, last year and an expedition, carried out last week, has now found the stern section about 600-700 metres away.

Video footage taken by remote cameras show the ship split at bulkhead 65, and this may have caused the disaster. At this stage, however, it is not possible to say whether the bulkhead failure caused the accident, or whether it was a consequence of other problems.

The expedition is part of a pounds 2m two-part survey which has been mounted after pressure from the relatives of the 44 people lost on board to try to discover what caused the loss. The second stage will take place early next year and will involve around 40 days of survey work which it is hoped will solve the 16-year mystery.

Sister ships of the Derbyshire were all reported to suffer structural problems - and one of them, the Kowloon Bridge, broke in two after running aground in 1986.

For many years, the Department of Transport refused to undertake a survey and it was only when evidence was brought back by the ITF that it bowed to pressure from the families. Yesterday, the three assessors carrying out the survey showed the video footage to the families before releasing it to the press. One of the assessors, Robin Williams, said that some of the families found it upsetting "but we tried to prepare them as best as possible". There was no sign of human remains.

The video clearly removes one possibility raised by the inconclusive inquiry into the disaster - that the Derbyshire had run into problems in high seas after losing its rudder.The rudder can be clearly seen in its normal position, and Mr Williams believes that an adjacent heap of mud will prove to hide the propeller - ruling out the possibility that it fell off. However, another 11 possible causes remain to be considered.