Eight suspected militants were shot dead by police Monday after they escaped from a high security jail in India by slitting the throat of a prison guard, an official said.

The members of the banned Students Islamic Movement of India (SIMI) had staged an overnight breakout from the prison in Bhopal by attacking a warder in their cell with sharpened prison-issue steel plates.

They then managed to scale several walls inside the prison by tying together bedsheets.

Police said they had been later cornered on the outskirts of the city in the central state of Madhya Pradesh but resisted efforts to take them back into custody.

“We asked them to surrender but they tried to break the police cordon,” Yogesh Choudhary, Bhopal's inspector general of police, told AFP.

“They were unarmed but attempted to attack the police with stones. We had to shoot them,” Choudhary added.

The prisoners had managed to make their way by foot to a village about 15 kilometres (10 miles) south of the centre of the city, despite a massive search operation.

The dramatic break-out happened on the night of Diwali, a major Hindu festival when revellers traditionally set off fireworks which can shroud the night skies in mist.

Some of the inmates had been awaiting trial for “terror related activities” for the last three years, although two of them had only been detained since February.

Police insist that there was no breakdown in security at the prison, which has a round the clock electronic surveillance system.

Indian authorities have accused SIMI of carrying out several deadly bombings and having links with Pakistan-based militant groups.

Police blamed the group for the serial bombing of Mumbai commuter trains in 2006 which killed 187 people, as well as bomb blasts in New Delhi.

The government banned the group in 2001 in the aftermath of the September 11 attacks in New York and Washington.

Hundreds of its members have been arrested in the past decade, but the group says it merely propagates “Islamic way of life” for Indian Muslims.