Malaysian police said a Pakistani man and two Malaysians were taken into custody "a few days ago" based on information provided by Thai authorities.

"We believe the suspects can help in the investigation...our arrest was made to assist the Thai police in the Thai bombing investigation," Khalid Abu Bakar, the national police chief, told reporters.

He added that one of the local suspects was a woman, and that there were no plans as yet to hand the three over to Thai police.

On August 17, a bomb went off at the Erawan Shrine in the heart of Bangkok, killing 20 people and injuring scores more. Most of the victims were Chinese tourists.

Thai authorities have so far arrested two men, whose nationalities remain unconfirmed, over the blast. They are still seeking a number of other suspects.

No group has claimed responsibility for the bombing. One theory is that the attack may have been carried out by militants from China's Uighur minority, or their supporters, as revenge for Thailand's forced deportation of 109 Uighur refugees in July.

The Uighurs, many of whom have their home in the northwestern Xinjiang region of China, have long accused Beijing of discrimination as well as religious and cultural repression, with scores fleeing to Turkey via Southeast Asia in recent years.

nm/ rg (Reuters, AFP, dpa)