The plight of a British military team trapped in a Mexican cavern erupted into a diplomatic controversy Wednesday with Mexico saying Britain may have been carrying out military training there without permission.
President Vicente Fox ordered a letter of protest sent to London and demanded an explanation for the ill-fated expedition that left five cavers and a guide trapped in the Alpazat caverns in the central state of Puebla.
"We are asking the British government to tell us whether these people are military personnel, and if they are, what they are doing there," the president said in Honduras, where he was on an official visit.
The planned three-day underground expedition by Britain's Combined Services -- which includes members of the army, navy and air force -- stretched into an eighth day of entrapment as floodwaters fed by incessant rains continued to block the cave's entrance.
So far, the Britons have rejected Mexico's offer of help, and said they were waiting for the arrival of two specially trained civilian cave divers from the British Cave Rescue Organization.
The cave's entrance is too narrow for conventional scuba gear to fit through.
The cavers remained about 270 feet below, in a well-stocked emergency camp inside an unflooded part of the Alpazat cave.
Fox said the crux of the diplomatic issue was that the Britons had entered on tourist visas and might have been doing more than simply exploring the mountains of Puebla.
Acting British Ambassador Vijay Rangarajan said Mexico's concerns that the cavers might have been doing anything other than exploring were "pure fantasy."
Six other members of the caving team have been waiting for their companions above the surface in Cuetzalan.
"It's an official military expedition to support adventurous training," said Stephen Whitlock, one of the six.
Asked about the fact that team members had entered Mexico in late February with just tourist visas -- and without notifying authorities of their caving trip -- Whitlock said, "There are no registration requirements for the sport of caving and cave expeditions in the state of Puebla."