Police in northeast India said Tuesday they believed workers on a tea plantation who bludgeoned their boss and his wife to death last month also ate parts of their bodies.

A crowd of 1,000 workers at the privately-owned M.K.B. Tea Estate in the state of Assam surrounded the plantation owner's bungalow last week. A mob then set it on fire in violence blamed on festering labour unrest in the region.

"Our investigations say that at least five plantation workers ate the flesh of the tea planter and his wife after they were brutally killed," Numol Mahatao, deputy police chief of Tinsukia district, told journalists.

"We suspect that about 15 people were actually involved in the crime although there were some 1,000 present there at the spot," the police official said. "We have identified all the masterminds and nine are in our custody so far."

Mahatao said the reports of cannibalism were based on a confession from one of the workers present during the attack.

Tea workers are notoriously badly paid and often housed in poor accommodation in remote areas. They have few protections from police and cannot take advantage of laws designed to guarantee them health care and fair working conditions, rights groups say.

The Indian Express newspaper said the violence was sparked by orders from the boss for 10 estate workers to vacate their quarters and by the detention of three employees by police over unspecified disputes.

"We are investigating the reasons that led to the attack. But whatever may be the reason, such acts of barbarism are unacceptable in this modern world," Assam Chief Minister Tarun Gogoi said on Tuesday.

Assam produces around 55 percent of India's annual tea production, which stood at 988.32 million kilograms (2.2 billion pounds) last year, and the state is home to more than 800 tea estates.

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