BANGKOK- Thailand's Interpol director said on Tuesday there was "no credible" threat of an attack by suspected members of Islamic State following a warning by the Russian intelligence service that 10 Syrians linked to Islamic State had entered the country.A document from Thai Special Branch police leaked to social media showed it had been warned by Russia's Federal Security Service that 10 Syrians linked to Islamic State had entered Thailand between Oct. 15 and Oct. 31 to target Russian interests.Confirmation on Friday that the document was real prompted Thailand to step up security around potential targets including the cities of Pattaya and Phuket, home to large Russian communities. Officials have called for calm.Thailand's Interpol director, Police Major General Apichart Suribunya, said that Interpol and Special Branch were both looking out for intelligence but that there was no credible threat of an attack in Thailand."We get warnings like this many times. There is no critical intelligence of IS presence in Thailand," Apichart told Reuters."There is no credible threat of an IS attack, not now. From Interpol, there is no critical intelligence and no credible threat of an IS attack in Thailand."