At least 40 people have been injured in religious clashes on a remote delta island in India's eastern state of West Bengal, police say. Fifteen of those injured in the clashes on Sagar island, at the confluence of the Ganges and the sea, were policemen. Supporters of the Hindu nationalist Rashtriya Swayamsevak Sangh(RSS) and local Muslim villagers clashed after the RSS set up a camp in the area. This caused unease amongst Muslims, who have a large population on the island. The RSS is active throughout India and is the ideological fountainhead of India's main opposition party Bharatiya Janata Party (BJP).