Mexico City - Eighteen of the 33 Cubans who were "rescued" from Mexican authorities by an armed commando last week have turned up in the US state of Texas, the Mexican Public Prosecutor's Office said Thursday.

The details given to US officials by the migrants themselves partly solved the mystery of their disappearance.

The Cubans explained how a wide range of intermediaries allowed them to escape from Mexican authorities and then to travel to the United States seemingly legally, with documents that were or at least looked real and with money in their pockets.

US government agencies contacted Mexico to say that the Cubans who had originally been detained by Mexican immigration officials were found "by US authorities on US territory, in good health condition and having suffered no physical damage at all."

According to US legislation dating back to 1966, Cubans receive automatic residency rights upon arrival on the US mainland.

Mexico, which wants to normalize its relations with Cuba, has threatened to send illegal immigrants back to Cuba.

The Cubans had been picked up by Mexican officials on June 6 along the country's eastern coast, a common beaching point for Cuban refugees who use the route on their way to the United States. Their boats usually take them to the Yucatan peninsula.

However, they disappeared six days later, after being taken by force from Mexican immigration officials as they were being taken by bus to the Tapachula facility in the southern state of Chiapas, on the border with Guatemala.

The strongmen travelling in two luxury vehicles stopped the bus, forced the seven official escorts and two drivers out of the vehicle and drove off with the occupants under their command, a police spokesman said last week. The empty bus, operated by Mexico's immigration department, was found later.

Mexican authorities said Thursday that they knew nothing of the whereabouts of the remaining Cubans and of three Guatemalans and a Salvadoran citizen who had been travelling with them on the bus.

Nine immigration officials and the two bus drivers were under arrest for questioning. They were believed to have assisted efforts to take the migrants from Mexican authorities.

Two Cuban-Americans were charged with illegally taking the migrants from Cuba to Mexico.

Mexican authorities gave details of the operation based on accounts given by Cuban migrants to US officials after they arrived there. Following the armed rescue in Chiapas - in which at least six masked men armed with rifles took part - the migrants said they were taken to a safe-house in the eastern Mexican state of Veracruz.

There, "they had photographs taken that were stuck on individual sheets of paper bearing the seal of (Mexico's) National Migration Institute."

With these documents, which ordered their exit from the country, they were then taken to the Veracruz central bus station, divided into groups and given enough money to travel to the United States.

"With the documents handed to them, one of the groups of immigrants who arrived in the United States said they went through two military checkpoints and two migratory filters without trouble, on the way from Veracruz to Reynosa by road on a passenger bus," the Public Prosecutor's Office said. (dpa)