Car bomb kills four in Indian Kashmir-police

SRINAGAR, India, Sept 12 (Reuters) - A car bomb killed at least four people and wounded 10 on Saturday, when it hit a police bus in Indian Kashmir's main city, police said.

The explosion, the deadliest in recent months, shook buildings around Central Jail, the main prison in Srinagar, Kashmir's summer capital. Three police and a woman were killed.

"It was a car bomb and it hit a police bus," Mohammad Amin, a police official said.

No militant group has claimed responsibility.

After relative calm, there has been a sudden rise recently in separatist violence across Kashmir, where officials say tens of thousands have been killed since a revolt against Indian rule broke out in 1989.

Indian security officials say Pakistan-based militant groups have stepped up efforts to push their members into Indian Kashmir before winter snow blocks the Himalayan mountain passes.

Kashmir remains at the core of a six-decade-long conflict between India and Pakistan, which both claim the region in full but rule in part.

India says Pakistan arms and trains Kashmiri separatist militants. Islamabad says it only extends moral support to the Kashmiri "freedom struggle".