In an intensified crackdown on illegal sand-mining from river beds and banks, the police on Friday seized a large amount of construction materials and arrested nearly 25 persons.

The police impounded 15 country boats and 14 mini-trucks from various parts of the district. The special drive, christened ‘Operation River Protection’, was headed by Superintendent of Police S. Surendran. The operation began at 5 a.m.

The surprise raid comes amid complaints of large-scale sand-mining. Simultaneous raids were carried out at Thalangara, Bangode, Chemnad, Thuruthi and Perumbal along the banks of the Chandragiri river.

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