The first of an estimated 15,000 Hmong refugees remaining from the Vietnam War era are leaving Thailand for the United States. The 25 members of three families of the minority ethnic group from Laos have been flown to America after spending three decades in a Thai refugee camp.

With the arrival of the former refugees in the United States, the U.S. government has begun to settle the last of the Hmong refugees left from the wars in Indochina.

An officer with the group that oversees the resettlement program, Pierre King of the International Organization for Migration, says there will soon be a steady stream of Hmong leaving Thailand.

"In the coming weeks we expect to move close to 4,000 Hmong, mostly on all-commercial airlines with groups of 35 nearly on a daily basis," said Mr. King.

Mr. King says all 15,000 refugees are to be resettled by the end of the year. Before leaving, they must be cleared by the U.S. government, a process that began several months ago.

The Hmong, an ethnic minority from the highlands of Laos, backed the U.S.-led battle against the communist Pathet Lao during the 1960s and '70s. Several hundred thousand fled to Thailand after the communist victories in Indochina in 1975. In subsequent years, 250,000 were resettled in a score of countries, though most of them went to the United States.

The rest have been living on the grounds of Wat Tham Krabok Buddhist temple 140 kilometers north of Bangkok.

Mr. King says some of the older refugees are worried about moving to a very different society far from home, but he says the IOM is trying to prepare the Hmong for their new lives.

"They have classes of 20 hours per week where they cover all the issues of cultural shock, all the issues of what they can expect in the United States for their new lives," he explained.

The classes are taught by Hmong refugees who were among the first to settle in the United States, in the 1970s.

Hundreds of thousands of Hmong-Americans live in America and many of them suffered serious problems in adapting to their new homes after they first arrived.

They have now established large communities in the northern state of Minnesota and the western state of California, which are expected to provide important support for the new arrivals.