Indian Prime Minister Narendra Modi vowed on Thursday to pursue, track and punish terrorists and their backers in a strong reaction to a deadly militant attack on tourists in Kashmir, where police have identified two of the gunmen as Pakistani.

India says it has revoked all visas issued to Pakistani nationals following a deadly attack by gunmen in Kashmir that killed 26 people, mostly tourists. In a statement issued on Thursday, India’s foreign ministry said all visas issued to Pakistani nationals stand revoked with effect from Sunday.