Indian officials say at least four civilians have been killed in firing by Pakistani troops along the volatile frontier in Indian-controlled Kashmir, in escalating violence in the disputed region that both countries blame the other for initiating.

Police said Wednesday that Pakistani soldiers continued targeting dozens of Indian border posts and villages with mortars and automatic gunfire for the sixth straight day in the Jammu region. At least 30 people have been injured.

Pakistan did not immediately comment.

Indian officials have called the violence a continuous violation of the cease-fire accord of 2003 between the rivals.

India and Pakistan have a long history of bitter relations over Kashmir, which both claim. They have fought two of their three wars since 1947 over their competing claims to the region.