At least 18 shellfish hunters died when they were trapped by fast-rising tides in treacherous Morecambe Bay in northern England, police said yesterday. Police reported 14 survivors and said the search was continuing.

　　The dead - 16 men and two women - were among a large group, all believed to be Chinese nationals, who were cut off from the shore at Morecambe Bay in Lancashire on Thursday evening as they searched for cockles, a shellfish delicacy that lives just below the surface of muddy sand.

　　Geraldine Smith, the local member of the British Parliament, said the difficulty of regulating cockle picking meant that it was "a tragedy waiting to happen."

　　"The cockles which were on the beach were worth a great deal of money, but very tragically I would imagine that those poor people who lost their lives were making very little of that money, and were probably victims of exploitation," Smith told British Broadcasting Corp radio.

　　The rescue was complicated by uncertainty over how many pickers were in the bay - the initial emergency report was of around 25 people but rescuers later acknowledged they had no idea how many were in the group.

　　"We have received unconfirmed reports that some people in the group may have left the area without telling us so the problem is that we don't know how many people we are looking for," said Coastguard spokesman Martin Collins.

　　Helicopters and lifeboats are being used in the search for those still missing. Land teams are also scouring the coastline near the bay.

　　Lancashire Deputy Chief Constable Julia Hodson said the 16 survivors were being interviewed by police at a recovery center set up near the bay.

　　Hodson said several interpreters had been called to help as police questioned the group, both to glean more information about others who might be missing and their immigration status in Britain.

　　"They may be here legally or illegally so we'll be working with the immigration service to examine exactly what the circumstances of them being here are," Hodson told a news conference.

　　The 310 square kilometer Morecambe Bay is notoriously dangerous, known for its fast rising tides and quicksands.

　　A British man and his 9-year-old son drowned in the mud flats two years ago after becoming disoriented in fog and trapped by the rapidly incoming tide.

　　Signs along the bay read: "Beware. Fast rising tides. Quicksands. Hidden channels."

　　Police said several of the recovered bodies were found on a sand bank in the northern part of the bay, several miles from Hest Bank where the group was reported missing.

　　Commander Harry Roberts, of the Royal National Lifeboat Institution, said none had any safety gear and some had stripped naked as they tried to swim to safety in the bitterly cold waters.

　　In August last year, police arrested 37 Chinese people in the Chatsworth area of Morecambe after concerns were raised about the scale of cockle picking on the sands at the bay.

　　Cockle picking is not illegal but locals complained that gangs from across Britain were flocking to Morecambe Bay, eager to get their hands on the lucrative shellfish, which are mostly sold abroad.