KUALA LUMPUR - Malaysian police said on Friday a third Turkish national has been detained, suspected of threatening national security, after two were held earlier this week.The detentions come amid concerns raised by US-based Human Rights Watch that Turks in Malaysia are being held due to pressure from Ankara.Turgay Karaman, the head of an international school, and Ihsan Aslan, a businessman, were arrested on Tuesday. Ismet Ozcelik, the director of a Turkish university, was picked up by police on Thursday, police chief Khalid Abu Bakar told reporters without elaborating.He said Ozcelik had known both Karaman and Aslan, but declined to comment on media reports that the men were linked to the Islamic State militant group or that they were supporters of US-based Muslim cleric Fethullah Gulen.Gulen is blamed by Turkish President Tayyip Erdogan for orchestrating a failed coup last year, a claim he and his followers deny.The detentions had not been made on the request of the Turkish government, Khalid said."Why would we wait for directions from abroad? We have our own country's laws," he said."People who threaten our security, we do not welcome them, these foreigners who come here and try to disrupt the peace."Ozcelik had been previously arrested in December and was facing charges, along with four others, of obstructing immigration officials from carrying out their duty.Rosli Dahlan, Ozcelik's lawyer, said his client had been held in remand for more than 50 days after the December arrest, and questioned why Ozcelik was being detained again."There was nothing about IS or any alleged terror links then," Rosli said.Rosli had told Reuters earlier that two Turks were reported missing in October and later discovered to have been deported to Turkey.Turkey has applied pressure on other countries that are home to institutions backed by Gulen, whose Hizmet movement runs about 2,000 educational establishments around the world.Phil Robertson, Asia deputy director of Human Rights Watch, said police should explain why the Turks were being held on security grounds without charge, adding that the detentions came at a time when Turkey was "actively pursuing perceived opponents all around the world.""(The police) need to reveal a whole lot more information about these cases before people are going to seriously believe that Ankara had nothing to do with it," he told Reuters.