The incident took place at Shamli, over 100 km from New Delhi, when a team of revenue officials and policemen went to question a sand mafia for alleged illegal mining of sand near the banks of Yamuna.
During his questioning, his henchmen attacked the team and injured the 'nayab tehsildar' (revenue official), a station house officer (SHO) and a police constable, police said, refusing to disclose the name of the sand mafia.
They were taken to a medical facility in Ghaziabad later where their condition is said to be serious.
Shamli's Senior Superintendent of Police (SSP) Abdul Hameed said that the team had gone to Shamli after receiving complaints of illegal mining of sand from the banks of Yamuna river.
No one has been arrested so far, the SSP said. Teams have been formed to nab the culprits.
"It is indeed a very shocking and serious matter. We will hound out the mining mafia," the police chief added.