Kuldeep (36), Mahendra (40) and Raju (16) died in the district hospital here, Superintendent of Police Umesh Kumar Singh said.
Three others - Vinay (30), Mehboob (40) and Amar (50) - have been referred to Lucknow hospital as their condition was stated to be serious, he said.
Prima facie it seemed that excessive consumption of liquor led to the deaths, the SP said, adding the case is under investigation.