The man, identified as Alam, was nabbed when he was swimming close to the wharf late last night. The incident, coming 10 days after the Chennai twin blasts on a train, which killed one person and injured 14 others, has kept police on tenterhooks.
A senior police official privy to the probe told PTI that preliminary investigations revealed he had sneaked into India through the West Bengal border, seeking employment.
It is not clear how he reached Chennai, why he tried to enter Ennore Port without permission and at such an odd hour. Ennore port, now renamed Kamarajar Port, is the third major port of Tamil Nadu.