By Fayaz Bukhari

SRINAGAR, India (Reuters) - Indian security forces killed seven militants in two gunbattles that also left a police officer dead in Kashmir on Sunday, as tensions in the region ratcheted higher and street protests against Indian rule grew.

Three of the militants were killed after they tried to storm the government secretariat in Poonch, near the de-facto border with Pakistan, which lays claims to the Himalayan region.

"One policeman was killed, while another police officer and civilian were injured as militants tried to storm the building. The police repulsed the attack and the militants took refuge in nearby buildings," said a senior police official, adding that the three militants were killed after a day-long gunbattle.

Separately, a senior army officer told Reuters that the army foiled two infiltration attempts by militants near the line of control with Pakistan. Four militants were killed in one of the gunbattles. Infiltrators attempting to cross the border were pushed back in the second clash in which no one was killed, authorities said.

Large swathes of Kashmir remain shut down for a third month, as Indian authorities struggle to contain violent demonstrations triggered by the killing by security forces in July of a young militant commander who was revered by some Kashmir youth.

On Saturday, two people were killed in new protests in Kashmir, taking the death toll to 75 since protesters took to the streets following the killing of Burhan Wani, the commander of the Hizbul Mujahideen group.

There was more trouble on Sunday when police fired tear gas to disperse a mob in Karimabad in southern Kashmir, and at least 50 people were injured in the clashes, the police control room said.

The violence in Indian Kashmir has reignited tensions with Pakistan as New Delhi blamed its neighbor for stoking further trouble there by pushing militants across the heavily militarized border that divides the region.

More troops have now been deployed on the Kashmir frontier to foil such infiltration attempts, officials said.

Pakistan denies giving material support to the Kashmir guerrillas but says it provides moral and diplomatic support in Kashmir's struggle for self-determination.

(Reporting by Fayaz Bukhari; Writing by Sanjeev Miglani and Euan Rocha; Editing by Peter Cooney)