India says it launched air strikes against Pakistan-based militants after a suicide bombing earlier this month.
Foreign Secretary Vijay Gokhale said the strikes targeted Balakot, but it is not clear if that is in Pakistan or Pakistani-administered Kashmir. He said several militants were killed.
Pakistan said it scrambled fighter planes in response.
The move represents an escalation of hostilities between the two nuclear-armed neighbours.
It is the first air strike launched across the line of control – the border that divides India-administered Kashmir from Pakistan-administered Kashmir – since a war between the two countries in 1971.
Mr Gokhale told a news conference that the strikes had targeted the militant group Jaish-e-Mohammad (JeM).
"A large number of JeM terrorists were killed. The strike avoided civil casualties," he said.
"Credible intel [intelligence] was received that JeM was planning more suicide attacks in India. In the face of imminent danger, a pre-emptive strike became absolutely necessary."
He said senior commanders of the group had been killed.
The latest incident follows a suicide attack on an Indian security convoy in Pulwama, in Indian-administered Kashmir, earlier this month.
BBC