Eleven persons were arrested on Sunday and several detained for questioning in connection with the clashes in Ghazipur district of Uttar Pradesh where a police constable was killed and several others injured in stone pelting during a protest by members of the Nishad Party.

The violence took place after a rally on Saturday by Prime Minister Narendra Modi. Over 90 persons were named in the FIR, including 30 named as accused.

Constable Suresh Vats was returning from his duty at the rally when the incident took place under the Nonhara area of the Purvanchal district.

Yesh Veer Singh, SP Ghazipur, said the constable was killed when the protesters started pelting stones as the police were "trying to clear the roadblock" created by them. The protesters had blocked roads at four places near the venue, he said. The constable succumbed to his injuries.

Chief Minister Yogi Adityanath took cognizance of the matter and announced an ex-gratia compensation of Rs 40 lakh to the family of the constable. He also directed the district magistrate and SSP to "take strict action against the unruly elements and immediate arrest and legal action against them," a government statement said.

Sanjay Nishad, president of the Nishad Party, demanded a detailed police investigation into the incident. "The BJP is trying to defame us with wrong allegations," he said.

Praveen Nishad, MP of Gorakhpur, and leader of the Nishad Party, while talking to The Hindu said Nishad Party had no role in the violence. He claimed activists of the party were staging a peaceful dharna when members of the BJP who were returning from the rally in vehicles started chasing and attacking the Nishad activists.

"Due to the attack, local villagers came to the support of our workers and this led to an altercation. The incident regarding the constable (stone-pelting) took place through the BJP workers," said Mr. Nishad.

The Nishads were demanding issuing of SC certificates for their caste under the name Majwar and implementation of a 2016 notification brought under the Akhilesh Yadav government, said Mr. Nishad.

"The present government is not giving us the certificates even though it is still valid," said the MP. Nishads are among the 17 most-backward castes in UP who have been over the years struggling for SC status.