Four Uighur men and four Malaysians suspected of human trafficking questioned over possible activities surrounding blast that killed 20 people

Eight people, including four believed to be ethnic Uighurs, have been detained in Malaysia for questioning in connection with last month’s bombing of a shrine in Bangkok that killed 20 people, a senior official has said.

The national deputy police chief, Noor Rashid Ibrahim, said they were detained in the past week in the capital, Kuala Lumpur, and in north-eastern Kelantan state.

Four of the eight were Malaysians involved in human trafficking, while the others were believed to be Uighur men who entered the country illegally, he said. While there is no evidence they were directly involved in the bombing, they are being investigated to see if they had any role in other activities surrounding the blast.

“Right now, there is no concrete evidence to show that they are directly involved,” said Noor Rashid.

He added that Thai police had been notified, and hoped they could help in identifying the men. Thailand will need to provide basic proof of their involvement in the bombing if it wants to extradite the suspects, he said.

Noor Rashid initially said the Uighurs had no documents on them and that their only offence was entering Malaysia illegally from Thailand. However, he later said they had passports but it was unclear if they were genuine.

The blast at the Erawan shrine in the Thai capital on 17 August also injured more than 120. Many of the victims were foreigners as the shrine is a popular destination for tourists and Thais alike.

In Bangkok, the Thai police chief, Somyot Poompanmoung, said he had not received any confirmation from the Malaysian police that the suspects were involved in the blast.

Thai authorities have arrested two suspects they say were linked to the bombing, but believe the actual bomber and the mastermind of the plot have fled the country.

Thailand has suggested that those behind the blast may have been from a gang involved in smuggling Uighurs from the Chinese region of Xinjiang, while others speculate they may be separatists or Islamist extremists angry that Thailand repatriated more than 100 Uighurs to China in July.

Uighurs complain of oppression by the Chinese government, and some advocate turning Xinjiang into a separate Uighur state.