BANGKOK • Thailand said yesterday it was looking for four Syrian nationals who have overstayed their visas, as the country is on high alert after a Russian warning of possible attacks by suspected Syrian members of the Islamic State in Iraq and Syria (ISIS).

The authorities did not suggest the four men were a security threat but said they were unaccounted for, and released their names and photographs.

Last week, a document from the Thai Special Branch police leaked to social media showed it had been warned by the Russian intelligence service that 10 Syrians linked to ISIS had entered Thailand in October intending to attack Russian interests.

The warning prompted Thailand to step up security around potential targets, including in the cities of Pattaya and Phuket, both popular with tourists and home to large Russian expatriate communities.

However, the Immigration Bureau said the four Syrian men being sought had entered Thailand between April and October, not in the timeframe specified by Russian intelligence.

"Of the four who are unaccounted for, we may just want to locate them to charge them for overstaying, that is all," Immigration Bureau commissioner Nathathorn Prausoontorn said.

Meanwhile, in neighbouring Malaysia, a part-time English teacher from Britain, who once fought as an Al-Qaeda militant in Afghanistan and Bosnia, was one of five men arrested for their involvement in terror groups.

Counter-terrorism officals said last Saturday that they nabbed the 44-year-old Briton together with a Bangladeshi, 25; a Nigerian, 29; an Indonesian, 31; and a 59-year-old Malaysian in a series of raids in Selangor, Kelantan and Johor between Nov 16 and Dec 1.

REUTERS, THE STAR/ASIA NEWS NETWORK