Police and intelligence services have begun a transnational investigation into revelations that at least two Chennai college students are now training with jihadist groups in Syria, highly placed intelligence sources have told TheHindu.

The revelations, the sources said, have come from Gul Mohamed Maracachi Maraicar, a resident of Cuddalore in Tamil Nadu who was stripped of his Singapore permanent residency and repatriated to India in February.

Mr. Maraicar, a former employee of information technology giant IBM in Singapore, told authorities in that country that jihadists had successfully recruited students from a college in Chennai. The investigation, the sources said, began with the disappearance of Tamil Nadu-born Singapore permanent resident Haja Fakkurudeen Usman Ali earlier this year. Based on information from an informant, Singapore’s intelligence services determined Mr. Ali had left Singapore for Syria on January 22, 2014, travelling through Turkey — where several jihadist groups operating inside the violence-torn state are now based.

In a statement released on Sunday, Singapore’s Ministry of Home Affairs said Mr. Ali, a supermarket manager, was being investigated for going to Syria “with the intention to undertake violence” in the ongoing armed conflict there.

It said the government had invoked the Internal Security Act to strip Mr. Maraicar of his permanent resident status. Mr. Maraicar is not being currently prosecuted in India, and TheHindu was unable to locate his legal representatives. Police sources said he was cooperating with investigations, and declined to name the students, saying their families were attempting to persuade their wards to return home.

Intelligence sources said Mr. Ali’s ideological radicalisation had begun with his contact with Mr. Maraicar.

In 2007, sources familiar with the investigation said, Mr. Ali visited Cuddalore as a volunteer on a religious missionary trip.

The two men continued maintaining close contact, which deepened after Mr. Maraicar became a permanent Singapore resident in 2008.

Mr. Ali, Singapore investigators found, first travelled to Syria in 2013 with financial support from Mr. Maraicar, training briefly in a camp housing Chechen jihadists. Later, he returned to the country, and served as a node for the Chennai students who were recruited to serve there.

In September, Syria’s ambassador to New Delhi, Riad Kamel Abbas, said jihadist fighters fighting his country’s government included Indian nationals.

Later, however, he said his remarks had been misinterpreted, and referred only to individuals of Indian origin, holding United Kingdom passports.