Adem Karadag Bangkok bombing
Bangkok bombing suspect Adem Karadag is escorted by Thai commando unitsPORNCHAI KITTIWONGSAKUL/AFP/Getty Images

Malaysian police have arrested three people including a Pakistani national in connection with the bomb blast in Thailand that killed 20 people and left scores injured on 17 August. Police said on Monday 14 September, that the Malaysian nationals and the Pakistani were "assisting with investigations".

Khalid Abu Bakar, chief of police, said that the suspects can help in investigations and that the arrests were made to assist the Thai police. "Malaysian and Thai police are working closely in cooperation," Bakar added.

So far no one has claimed responsibility for the blast at Erawan Shrine in Bangkok, in which 14 foreign tourists were killed. The Pakistani suspect was male while one of the local suspects was female, the police chief said, adding that there were no plans to move the suspects to Thailand yet.

While the Thailand police have been accused of "being overly casual" in their investigations, they did manage to get some leads with regards to the mastermind of the attack crossing into Malaysia. But the police in the neighbouring country were unsure if the main suspect was present there.

Earlier, a man arrested by the Thai police, had confessed to handing a backpack filled with the explosives to another man who then left it at the blast site. Security sources named the alleged mastermind of the attack as Abudureheman Abudusataer, a Chinese national from the Xinjiang region, reports said.

The 25-year-old suspect was arrested while he was attempting to enter Cambodia. Police had then said that the man admitted to have taken the heavy backpack containing a bomb from an apartment in an eastern suburb of the capital. From there, he took the bag to the Hua Lamphong railway station and handed it to a man, who was later seen on security cameras placing it near the Erawan Shrine.