By Manveena Suri and Rishabh Madhavendra Pratap, CNN

An Indian policeman’s hand was chopped off with a sword and six other officers were severely injured when they were attacked while enforcing  lockdown measures in northern Punjab state on Sunday morning.

The severed left hand of Harjit Singh, an assistant sub inspector for Punjab Police, was later reattached to his wrist following nearly eight hours of surgery.

The attack took place when a vehicle carrying seven men — who belong to the minority Sikh warrior sect known as the Nihangs — was stopped at a barricade outside a vegetable market in Patiala district, KBS Sidhu, a senior state government official, told CNN.

When police asked the men for valid travel passes, one of them took out a sword and cut off Singh’s hand.

Police officers show sharp-edged weapons recovered in Patiala, India, on April 12.

The injured officers, one with sword wounds to his back, were taken to the Postgraduate Institute of Medical Education and Research in Chandigarh.

“I am happy to share that a 7 and a half hour long surgery has been successfully completed in PGI to repair the severed wrist of ASI Harjeet Singh. I thank the entire team of doctors and support staff for their painstaking effort. Wishing ASI Harjeet Singh a speedy recovery,” the state’s chief minister Amarinder Singh

“The police didn’t even take out their arms and you attack them and cut off the hand of an innocent person? This cannot be tolerated and strict action will be taken …Once more, I am telling all of Punjab, I am warning the people that strict action will be taken against those who don’t follow the curfew,” Singh said.

Following an hour-long operation at a local gurdwara (Sikh temple), police arrested the seven accused men. A further investigation is underway.

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