PATNA: A group of upper-caste men shot dead four lower-caste fishermen in eastern India, for refusing to hand over their catch, police said Monday.

The victims were killed late Sunday while fishing at a pond in their village in the impoverished state Bihar, senior state police official Jitendra Rana told AFP.

“They were killed by a group of armed upper-caste people after they refused to share the fish caught by them,” Rana said, adding that another victim had been “seriously injured” in the incident.

Angry over the killings, scores of villagers halted traffic on roads and set tires alight on Monday near Paliganj town, some 55 kilometres from state capital Patna, demanding the accused be arrested.

Police are searching for seven men for questioning, based on a description given by the injured victim, Rana said.All of the victims were members of the impoverished Bind caste, which traditionally makes reed mats.

India's low-caste Hindus, who make up more than 15 per cent of the 1.2 billion population, are often victims of violence from upper-caste landlords.

While the Indian government banned caste discrimination at independence from Britain in 1947, it persists throughout the country, particularly in rural areas.

In some places, lower castes are banned from drawing water from the same wells as higher castes, cannot enter the same temples and are expected to bow and give way when higher-caste Hindus pass by.