Six persons, including five of a family, were killed on Monday in violence arising out of bad blood in Fatehpur village of Rudrapur area in Uttar Pradesh's Deoria, police said.
The incident took place in the Lehda Tola area in the morning, they said.
Former district panchayat member Prem Yadav was attacked with sharp-edged weapons and killed by his rival Satyaprakash Dubey and his family, Special DG Prashant Kumar said.
In retaliation, Yadav's supporters from Abhaipur attacked Dubey's house and killed Dubey and five of his family, he said.
The violence erupted out of a land dispute the two families were locked in.
Two persons have been arrested in connection with the killings, Kumar said.
Chief Minister Yogi Adityanath has directed the Commissioner of Police and the Inspector General to take strict action against the guilty.
He also condoled with the bereaved members of the two families and directed officials to ensure the best treatment to the injured.
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