Citizenship Act protests: Police posts and vehicles were vandalised in many parts of Lucknow.

At least one person died in Lucknow on Thursday from what authorities called "alleged firearm injury" during violent protests against the Citizenship (Amendment) Act. The police cracked down on protesters using tear gas and batons after vandalism, arson and stone-throwing erupted during a demonstration in the Uttar Pradesh capital against the contentious law.

"Mohammad Wakeel, 25, died of firearm injury here," King George's Medical University (KGMU) Trauma Centre in-charge Sandeep Tiwari told news agency PTI. "Two other patients are undergoing treatment in the trauma centre and one of them has firearm injury," he added.

Anti-citizenship law protesters hurled stones and damaged police outposts and a number of vehicles mainly in the Old City areas of Lucknow, forcing the police to use tear-gas shells to control the situation. Mobile internet was suspended in parts of the city late in the night.

The protesters torched a state-run bus at Parivartan Chowk, close to the district magistrate's office, and torched a police post in Satkhanda area.

Another police post was damaged in old Lucknow's Madeyganj, where police fired tear-gas shells after protesters smashed vehicles parked outside a police post.

"We have arrested 55 people. We will monitor CCTV footage. We will not spare anyone. Firing has not taken place from our end we will investigate it. Tomorrow there are Friday prayers as well. We will make sure that everything goes smoothly," Uttar Pradesh Police Chief OP Singh said.

When protesters in other parts of Lucknow hurled stones at police, they were lathi-charged. In several areas, including Hasanganj, policemen had a tough time tackling the protesters, who adopted a "hit-and-run" tactic, officials said. A few policemen were injured in the violence.

At Parivartan Chowk, which appeared to be the epicentre of the agitation, policemen faced brickbats and a number of television news vans were set on fire.

The gates of the nearby KD Singh metro station were shut to keep protesters from gathering at Parivartan Chowk.

The violence against the amended law led to panic among residents and forced traders in many markets, including the busy Hazratganj area, to shut their shops.

TV footage from different parts in the capital showed smashed vehicles, broken glass and rocks. Many stone-throwers had their faces covered with masks or handkerchiefs.

The situation improved only by the evening.

"The situation is under control and there is no need to panic. Those who created trouble are being identified," IG (Law and Order) Praveen Kumar told reporters.

Divisional Commissioner Mukesh Meshram said officials were scanning CCTV footage to identify those who damaged property.

"We will ensure that those who damaged property compensate for the loss," he said.

Taking a strong note of the violence, Chief Minister Yogi Adityanath warned his government will exact "badla" (revenge) on those involved in damaging public assets by "auctioning" their properties to compensate for the loss.

"There is no place for violence in democracy. In the name of opposing CAA, Congress, SP and Left parties have pushed the entire country into the fire. There was violence in Lucknow and Sambahal and we will deal with it strictly. All properties of those involved in damaging public assets will be seized and auctioned to compensate for the loss," Yogi Adityanath said.

UP government spokesperson and senior minister Shrikant Sharma said it was "highly unfortunate" that the opposition parties were "misleading" people, particularly the students, and urged them to cease doing so.

(With inputs from PTI)