At least 31 people have been killed in an explosion outside a mosque in the western Indian state of Maharashtra.

The blast took place in Malegaon town, 260km northeast of Mumbai, India's financial hub.

Police said thousands had gathered at the mosque for Friday prayers, adding that they were not sure if the blast was caused by a bomb or by a cooking gas cylinder exploding accidentally.

The blast came days after Manmohan Singh, India's prime minister, said that intelligence agencies had warned of more terrorist attacks across the country, possibly on economic and religious targets as well as on nuclear installations.

India has been on a heightened security alert after a series of bombs on commuter trains in Mumbai killed 186 people in July.

The attack was blamed on extremist Islamist groups with links across the border in Pakistan.

Malegaon has suffered religious violence in the past. In May, police recovered a cache of explosives and automatic rifles from the region based on information they said was provided by arrested extremist Islamists.

Photo Caption

An Indian soldier