Prime Minister Prayut Chan-o-cha yesterday instructed relevant agencies to be on alert after Malaysia revealed that a suspect linked to the Islamic State (IS), Muhammad Muzaffa Arieff Junaidi, had possibly fled to Thailand's deep South.
Muhammad, 27, from Malaysia's Kelantan state, is believed to have been running an IS cell. Six suspects linked to that cell were arrested in March in several Malaysian states.
"He managed to escape to southern Thailand with an M4 Carbine rifle and a pistol on March 22. He is also involved in smuggling weapons from southern Thailand," Inspector-General of Police Khalid Abu Bakar said.
Prayut said Thai authorities were ready to co-operate with Malaysia on a joint investigation and extradition of the suspect, but he urged the media not to play up the issue.
"Please don't play up the security matter. It's dangerous," Prayut said.
The Thai Army has contacted Malaysia for more information, Fourth Army Region Commander Lt-General Piyawat Nakwanich said.
There is no active IS movement in the deep South, he said, adding that border control authorities are very strict on cross-border movements.
There have been no reports of Muhammad entering the Kingdom, chief of Thai Immigration Bureau Natthorn Prausoonthorn said.
More than 6,800 people have been killed in the ongoing violence in Thailand's deep South since 2004. Authorities in Bangkok have said the situation in the predominantly Muslim region is a domestic affair.
In Malaysia, four men and two women, aged between 26 and 41, were picked up by Bukit Aman Special Branch Counter Terrorism Division following raids in five states, according to The Star newspaper.
The first arrests involved two men in Kelantan on March 24 and 25, Khalid said.
"We believe they were involved in smuggling weapons from southern Thailand for the terror group," he said yesterday.
A 26-year-old student was picked up at Kuala Lumpur International Airport on April 4 after she went to Turkey on August 29 last year with the intention of going to Syria to join IS, Khalid said.
"However, while waiting for further instructions from militant Muhammad Wanndy Mohamed Jedi, the suspect was detained by Turkish authorities on February 5," he said.
Two more arrests were made - of a 41-year-old jobless man, and a 32-year-old woman who worked as a factory technician - in Malacca and Johor respectively, Khalid said.
"We believe they were actively promoting IS propaganda via the Google Plus app," he said.
The sixth arrest was of a 41-year-old man in Penang state on April 25. He is believed to have promoted the IS struggle via 15 Facebook accounts since 2014.
It is believed he was also planning to attack Shi'ite mosques in Penang, Khalid said.