The Railway Protection Force (RPF) personnel seized 700 kg of rice, originally meant for distribution through fair price shops, at Ambur on Saturday.
On receiving information about rice smuggling on trains at Vellore, Ambur and Vaniyambadi, RPF personnel at the Ambur railway station conducted checks in the unreserved compartments of the Brindavan Express.
They discovered bags of rice stacked under the seats with the owners nowhere in sight.
The consignments were handed over to officials of the Civil Supplies Department at Ambur. After they completed the investigation, further action would be taken under the Prevention of Blackmarketing and Maintenance of Supplies of Essential Commodities Act, a civil supplies officials said.
The Ambur railway police have registered a case and are trying to locate the smugglers.
Residents pointed out that rice and other materials were being smuggled to towns in Andhra Pradesh by road without deterrence.
They added that offenders used their own two-wheelers for transport, which often gets ignored by the officials.