PHUKET: Investigation of human trafficking in Thailand is likely to swing to Phuket after three men transporting 19 boatpeople were arrested at a vigilante checkpoint north of the holiday island early today.

One of the arrested Thai men said their cargo of people was being taken to Phuket.

The checkpoint, on the main road north from Phuket through the provinces of Phang Nga and Ranong to Thailand's border with Burma, has been set up by local residents in a bid to halt all human trafficking along the Andaman coast.

A team of officers working for the district chief of the town of Takuapa, Manit Pleantong, staff the roadblock around the clock. Normally, only the police or the Army run checkpoints.

About 1.30am today, roadblock staff spotted a four-door pickup truck approaching. But the vehicle stopped short of the roadblock and its human cargo of 10 women and nine men were unloaded.

As the empty vehicle approached the checkpoint, the boatpeople were made to walk around the roadblock in the dark, through neighboring jungle.

Realising what was happening, the checkpoint officials waved the pickup through - then pounced as the 19 men and women rejoined the vehicle a little way down the road for the trip south to Phuket.

The group is the latest among hundreds of boatpeople who have been arrested along Thailand's Andaman coast in the past couple of weeks.

Thousands of others who have sailed from Bangladesh and Burma in the past month are missing, whereabouts unknown. Their families have not heard from them.

The latest apprehended boatpeople were bound for the small island of Koh Sireh off the east coast of Phuket, just a few minutes' drive over a roadbridge from the island's capital, Phuket City.

The plan was to drop the human cargo short of the bridge that links the mainland to Phuket, where there is a large police checkpoint, then transfer them by traditional longtail boat to Koh Sireh, which remains home to local fishing communities.

According to one of the boatpeople, they were eventually hoping to reach Pattani, a Thai province not far from the border with Malaysia.

One of the three Thai men said they were being paid 2500 baht a head to transfer the group to southern Thailand.

Khun Manit said: ''We want to end the horrors of the trade in humans along the coast of Thailand. This can't go on.

''There is no point in Thailand pretending that what is happening is not happening. I hope that other district chiefs will join this fight to save Thailand's reputation.''

Many boatpeople are abused, raped and sometimes killed in secret jungle camps in Thailand close to the border with Malaysia as traffickers extort cash by ransoming their captives to relatives and friends.

Along the Andaman coast over the past few weeks, the Takuapa district chief and Buddhist, Christian and Muslim activists have carried out their own arrests to expose the scale of the human trafficking they say is taking place.

Conflicts are emerging between local police and authorities who insist the unwanted arrivals are illegal immigrants and rebellious residents who say the boatpeople are sometimes clearly victims of human trafficking.

Limited budgets mean local officials often prefer to have the unwanted arrivals declared illegal immigrants so they can speedily be transferred out.

The largest group to arrive recently, 259 men, women and children, discovered near the town of Kaper, were due to be trucked to the Thai-Burma port of Ranong yesterday as ''illegal immigrants''.

When Immigration deports ''illegal immigrants,'' the stateless Rohingya among them, unable to reenter Burma, usually quickly find themselves in the hands of traffickers and sailing south again.

Thailand was downgraded to Tier 3, the lowest level, on the US State Department's Trafficking in Persons register earlier this year. Most countries take three years and have to demonstrate effective change to rise off the bottom rung.