"The Navy arrested the 53 people on board a suspicious vessel 60 nautical miles east off the coat of Hambantota (deep southern province) yesterday," police spokesman Superintendent Ajith Rohana said.
They were later produced in court and remanded till June 20.
Rohana said this was a continuation of several incidents of illegal immigration scams in the recent weeks.
He said previously some 11 people were arrested in the north western town of Puttalam while 11 women were arrested in the central town of Badulla.
Additionally, the police's Colombo Fraud Bureau had arrested 119 people. All were in the process of leaving for Australia through illegal means.
"This has shown that Sri Lanka has become a centre for illegal migration scams", Rohana said adding that mostly the minority Tamil and Muslim community youth have fallen victim of the scams.
In separate case, police arrested some 53 people, including 21 Afghan nationals and 5 Pakistanis, from lodging places in Colombo and the western coastal town of Negombo last night.
