The local officials in Marib, speaking on condition of anonymity because they are not authorised to deal with security issues, said tribal gunmen on Wednesday kidnapped the two Austrian tourists and probably took them to an area called Abeda.

Police officials, also speaking on condition of anonymity because they are not allowed to deal with the media, confirmed the kidnapping of two foreign tourists, but said they were not sure of the nationality of the two.

Tribesmen kidnap Westerners from time to time in Yemen, often to try to force concessions from the government. The hostages are usually released unharmed, but several were killed in 2000 when security forces carried out a raid to force their release.

The police officials said the kidnappers were from the Abeda tribe and that government forces had been sent to the area.

Abductors' demand

Tribal members in Marib, contacted by telephone from San'a, said the kidnappers had demanded the release from detention of two men from the Abeda tribe, but did not say on what charges the two were detained.

Two Swiss tourists were kidnapped in the same area last month, but were released two days later. They were kidnapped by members of the al-Jizah tribe in an apparent effort to force the government to release a brother of a kidnapper, who had been arrested on charges of stealing a car.

It was not clear if the government had made any concessions in that case.