A GROUP of 306 illegal Chinese immigrants are in a Mexican jail after the failure of their attempt to be smuggled into the United States. The Chinese, mainly young men in their 20s from Fujian province but including 16 women and 10 children, represent the latest in a series of failed smuggling efforts. Similar-sized groups have been arrested in the last few months in Singapore, at Kwajalein in the Marshall Islands, and off San Francisco. But two small groups of around 25 Chinese managed to evade arrest in the Mexican port of Ensenada, where this group was originally taken into custody. They may already have sneaked across the border into the US. Mystery surrounds the route by which the Chinese crossed the Pacific and arrived in Mexico. Under pressure from some members of their group the Chinese are refusing to reveal details to the Mexican authorities. There are indications that the Chinese took 40 days to reach their entry point of Punta China, 40 kilometres south of Ensenada, possibly via the central American state of Panama. They may have stayed in a ''safe house'' near Ensenada for as long as two months before a tip to the Mexican police resulted in their arrest. As with the earlier groups, around US$30,000 (HK$231,000) per person was promised once the illegal immigrants arrived in San Francisco's Chinatown. The news agency Agence France Presse said last night US authorities were holding a freighter packed with 237 Chinese and eight Koreans in international waters off the Bahamas in the Caribbean. Coast Guard officials boarded the 44-metre Mermaid 01, now 50 kilometres east of Mayaguana island in the Bahamas, almost a week ago after chasing the freighter for several days. Judicial sources in Paris said French police have arrested eight Chinese illegal immigrants and two Vietnamese frontier runners trying to smuggle the group into France through the French-Spanish border.