Sixteen of the men were interviewed by the state-appointed Committee of Enquiry into the riot in the Little India area, The Straits Times reported today.
The riot was sparked by a fatal accident involving an Indian national.
The 53 people had allegedly obstructed the police or failed to obey police order to disperse during the riot, in which 39 Home Team officers, including policemen, were injured and 25 police and Singapore Civil Defence Force vehicles damaged.
They were deemed to have posed a threat to the safety and security of Singapore, conditions that allow the authorities to deport them under the laws such as Immigration Act.
Twenty-eight Indian nationals were arraigned on riot charges and would have their cases heard in court on Monday.
Meanwhile, police have warned 200 other South Asian workers who were at the scene of the riot. They have been issued advisories to obey the law and would be allowed to remain in Singapore and work.
Foreign Minister K Shanmugam has stressed that the repatriation of the 53 is administrative decision rather judicial.
Under the Immigration Act, the government could ask an individual to leave once it has been determined that he acted contrary to Singapore's interests or acted in a manner prejudicial to public security or safety, Shanmugam said.
Earlier this week, a civil group had questioned the "arbitrary deportation" of these people, citing the United Nations Special Rapporteur on the Human Rights of Migrants.
The repatriation is being done in groups. A Bangladesh national was also being deported.
Some 400 South Asian workers rioted when 33-year-old Sakthivel Kumaravalu was fatally knocked down by a bus on the night of December 8.
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