Srivara is in charge of the probe into the attacks in Prachuap Khiri Khan’s Hua Hin district and Trang, Phuket, Surat Thani, Phang Nga, Krabi and Nakhon Si Thammarat provinces which killed four people and injured dozens more.

He said the probe had progressed beyond 50 per cent with three arrest warrants issued.

He said the three wanted men were believed to be hiding in Southern border provinces.

His team would check the scenes of the arson attacks in Krabi and Trang where cellphone and power bank fragments were found, leading investigators to determine they were fire bombs.

“If there was clear evidence, we would also apply for more military court-issued arrest warrants for all the provinces,” he said adding that the investigations in Hua Hin and Trang had progressed the most and only official confirmations were needed to conclude them.