"Indian aircrafts intruded from Muzafarabad sector. Facing timely and effective response from Pakistan Air Force released payload in haste while escaping which fell near Balakot," tweeted Major General Asif Ghafoor, spokesperson of Pakistan Armed Forces.
"No casualties or damage," he said.
However, while there was no confirmation from Indian Air Force, sources in the government said "the fact that Pakistan has admitted" suggests something big has happened.
The Home Ministry has alerted border areas in the northern and western states, sources said.
Former military officers have welcomed the government decision. "Finally, I am glad Prime Minister has walked the talk," Lt Gen (retd) Raj Kadyan told a private television.
