Clashes among communist militants in a recently merged group left eight fighters dead in India's volatile northeastern Bihar state, police said Saturday. Members of the outlawed Maoist Communist Center killed four members of the rival People's War group Friday night in Raghunathpur village in Aurangabad district, said Sunil Kumar Sinha, district police chief. The killings came in retaliation for a Thursday night attack against four Maoist Communist Center members, allegedly at the hands of People's War fighters, Sinha was quoted as saying by The Associated Press. Earlier this year, the two groups merged to become the Communist Party of India (Maoist), but their cadres have continued to clash with each other in Aurangabad, an MCC stronghold, he said. Aurangabad is located 80 kilometers (50 miles) west of Bihar's capital Patna. Caste clashes and violence involving communist rebels often takes place in Bihar, one of India's poorest and most lawless states.