Chennai, Sep 5 : Tamil Nadu's special police team has started a detailed investigation into the arrest of 13 Sri Lankan Tamils arrested from Kollam, Kerala on Monday morning. Special police teams including sleuths from the elite 'Q' branch of the Tamil Nadu police are in Kollam to interrogate those who are under the custody of the Kerala police. A senior officer with the Tamil Nadu police told IANS that the investigation is centered around two agents who were involved in bringing these people from Sri Lanka to India. The central intelligence agencies have given tip-offs about some people who have landed in Chennai and other airports of Tamil Nadu being missing even after their visit visa period had expired. While only 13 people are under the custody of Kerala police for trying to illegally move to Australia, Tamil Nadu police suspect that there may be more people in hiding as illegal human trafficking by the sea route is not possible with 13 people. It may be noted that a fishing boat comprising of 243 people including children and pregnant women had illegally left the shores of India from Maliyankara boat jetty near Munambam in Kochi on January 12, 2018. There was no information about the boat or its occupants including the kingpins of the racket who had also left in the boat. The intelligence bureau had then given inputs that the 243 had left for Australia but whether they have reached the shores of that country or whether they perished in the sea is still a mystery. The central agencies and the Tamil Nadu 'Q' branch police do not want a repeat of such a situation and have already swung into action to prevent any illegal trafficking from the shores of Kollam. Sources in Tamil Nadu police told IANS that there is proper coordination between the police of Kerala and Tamil Nadu and that the investigation is on track. /IANS