The team, led by mining inspector Archana Choudhary, spotted the sand-laden vehicles near Panjrakala village, about 25 kms from the district headquarters, and stopped them for checking, District Mining Officer Shivnath Prasad Patel told reporters.
As the team was taking the tractor-trolleys to Dehat Police Station, the attackers pelted stone sat them causing injury to constable Hemant Raj, he said.
The team impounded 5 to 6 tractor-trolleys carrying mined sand without any valid papers.