British cavers held by Mexican authorities

When Operation Cuetzalan Tiger swung into action early last week, its aim was to provide a group of off-duty British soldiers, sailors and airmen with a month of quiet exploration of the darkest reaches of Mexico.

When Operation Cuetzalan Tiger swung into action early last week, its aim was to provide a group of off-duty British soldiers, sailors and airmen with a month of quiet exploration of the darkest reaches of Mexico.

By yesterday what had started as an "adventurous training exercise" of Latin America's largest cavern complex by a joint-services caving club had become what one Foreign Office official in London bluntly described as a "diplomatic dog's breakfast".

The 13 members of the British team, including six men who had to be rescued from the remote Alpazat cave system after becoming trapped for eight days by flood water, were last night being "interviewed" by immigration officials after the Mexican government ordered they be taken to a detention centre in Mexico City.

The official inquiry into whether they have broken Mexican visa laws capped a calamitous week which put the hitherto low-profile Combined Services Caving Association at the centre of full-blown international incident complete with a rebuke from a president and allegations of clandestine uranium prospecting.

A senior Mexican minister made clear the lack of amusement in the country at the activities of the Britons - two civilians and 11 members of the Army, Royal Navy and Royal Air Force - by ordering a criminal investigation of Operation Cuetzalan Tiger's compliance with strict immigration rules.

Armando Salinas, the deputy interior secretary, said: "They will be placed in the custody of immigration authorities. We have reason to suppose that their actions could touch on our immigration law. Statements will be taken regarding their activities to determine if these people violated the general law... Their stay was legal as tourists but there are indications that their activities were not of this type."

The row was centred on whether the British team, who had financed most of the £15,000 cost of their four-week expedition themselves, had followed the correct procedure before they entered Mexico to explore and map the Alpazat caves, a labyrinthine 60-mile network near the town of Cuetzalan in the centre of the country, 110 miles north-east of the capital.

The Mexican embassy in London said the tourist entry obtained by the team would cover normal leisure activity such as caving. But the group's plans to produce a detailed map of the system required a special scientific visa, which had not been sought.

The matter was exacerbated by separate legislation which bans training by foreign military forces on Mexican soil.

Such was Mexican anger about the issue that the foreign relations department said it had expressed "profound concern" to London about the expedition and the country's President, Vicente Fox, said he would be sending a "protest and demand for clarification" from Downing Street.

The Ministry of Defence in London was fighting a rearguard action to defend its employees' conduct last night, while anxious not to further ruffle Mexican feathers.

An MoD spokesman said: "This was not a formal military exercise. It was an adventure expedition by personnel which had additional training benefits in areas such as leadership, endurance and self-reliance.

"When there have been previous expeditions to the same caves, a tourist visa is all that has been required. Obviously we will now be reviewing that."

The Foreign Office refused to be drawn into the row, saying only that it was "enormously grateful" to the Mexican authorities for their assistance in the rescue of the trapped team members. One diplomat admitted to embarrassment at the saga in Whitehall, saying: "It has been a public relations disaster."

Mexican irritation at the apparent high-handedness of their guests was increased when, after six of the team became cut-off by heavy rain which flooded a "sump" or subterranean U-bend in the caves, the Britons refused offers of local help and flew two specialist civilian divers from London instead.

The perceived show of British arrogance fuelled speculation in parts of the Mexican media that the highly trained military personnel had something to hide.

One newspaper, Independiente, reported rumours - subsequently dismissed by the Mexican authorities - that the cavers were looking for uranium ore and had specialist equipment to detect it. The equipment turned out to be safety sensors for radon, a radioactive gas.

For the six trapped members of the team, who emerged looking bearded and bedraggled from their captivity, spent eating pasta with cheese and instant chocolate cake, the scale of the row and attending media coverage came as an unwelcome surprise.

Jonathan Sims, a former Army officer who was rescued in the early hours of yesterday, said the team had never been in any danger. "The thing is, everything went as planned," he said. "We thought we might have a problem (with flooding rain water) so we put in a plan.

"We had food in there, we had communications. The unfortunate thing is we got too much media attention."

As relatives of the team members waited for news of their fate, sources on both sides seemed anxious to draw the affair to a close.

One Mexican diplomatic source said: "There should not be too much alarm about taking the men into custody. They have probably been punished enough. I think they will be interviewed and then put on a plane home."