A group of hammer-wielding vandals severely damaged the mazar of 18th-century Sufi poet Baba Bulleh Shah in Mussoorie on Saturday night, with a minor Hindutva outfit claiming responsibility.

Dehradun district police have registered an FIR against three named and a half-dozen unnamed accused on a complaint from the Baba Bulleh Shah Committee, but have said action would be taken only after a probe.

Muslim community leaders in Uttarakhand capital Dehradun, about 40km from Mussoorie, have threatened to march to the mazar (shrine) if arrests aren’t made soon.

According to the complaint, “some members of a Hindutva group barged into the premises late on Saturday night and vandalised the structure, built on private land”, Mussoorie (police) circle officer Manoj Oswal said on Monday.

A video circulating on social media shows about 10 people hitting an elevated structure with an arched top, resembling the mazar, with hammers and egging each other on to destroy it completely, while chanting “Jai Shri Ram”. Some of their faces are visible in the electric lights.

A man, understood to be a mazar committee member, appears to be trying to dissuade them.

Shah, an 18th-century reformer, is considered the “Father of Punjabi Enlightenment”. His mystical and unorthodox beliefs and contempt for dogma and rituals brought him into conflict with Islamic hard-liners, forcing him to spend much of his life fleeing from one place to another.

Local Muslims said the mazar, built on a local private school’s grounds in Bala Hisar, Mussoorie, had existed at the site for the past 100 years.

Bhupendra Chaudhary aka Pinki Chaudhary, president of the Uttar Pradesh-based Hindu Raksha Dal, claimed responsibility for the attack and “thanked” his “team in Uttarakhand”.

“The team of Hindu Raksha Dal sent the 70-year-old mazar of Bulleh Shah back to Pakistan,” he wrote on social media.

Chaudhary had been arrested three weeks ago on the charge of distributing swords among Hindus in Ghaziabad. He organised a “victory march” in the city after being released on bail on January 15.

Naeem Ahmad, a member of the mazar committee, alleged police inaction.

“The criminals had released a video on Thursday declaring they would remove the mazar if the government didn’t do so within a few hours,” he said.

“Now they have done what they said they would. The police remained inactive.”

Abid Qureshi, a Dehradun resident, said: “We may march to Mussoorie any day to give a fitting reply to these criminals. They have no right to target our legal private properties.”

He added: “We want the criminals behind bars immediately. Else, we will be forced to start a massive movement in the state.”

A purported Hindu Raksha Dal member, Vikas Verma, who claimed he was part of the team of attackers, told local reporters: “Bulleh Shah was born in Multan, Pakistan. We don’t need his fake mazar here. It was built on the land of a school.”

The FIR does not name Verma.

The circle officer said: “We are verifying the veracity of the video. Further action will be initiated against the accused after the inquiry is complete.”