The police opened fire in the air in Assam's Bongaigaon district on Saturday morning to disperse a mob at a market that attacked the security personnel when asked to abide by the lockdown order, an officer said.
None was injured in the melee, he said.
People had gathered in large numbers at meat and poultry shops of Bhawlaguri market in the district without maintaining social distancing norms.
As police intervened, most of them dispersed only to return with machetes and stones to attack the officers on duty.
The police personnel, when pelted with stones, resorted to lathicharge and opened fired in the air to quell he unrest.
Additional police forces rushed to the site and cordoned off the entire area, the officer said, adding that four persons have been arrested in this connection.
On Friday, too, both vendors and customers at Folimari Budhbari market in Dhubri district had attacked police personnel, who were trying to enforce the lockdown order - imposed by the government to contain the spread of Covid-19.