Nine army troopers were killed and 14 wounded when a massive roadside bomb took out a bus carrying troopers at Narbal, 15 km from Srinagar on the Srinagar-Uri highway on Saturday afternoon.
The bus was part of an army convoy moving from the frontier Chowkibal area in the north Kashmir Kupwara district to capital Srinagar.
A defence spokesman in Srinagar said nine army troopers died on the spot, while more than 14 injured were shifted to hospital.
The army had to press into service helicopters to lift the injured to the army base hospital in the high-security Badamibagh cantonment area.
Helicopters were seen making sorties between the blast site and the base hospital to make medical aid available immediately to the injured, some of whom are stated to be in critical condition.
Police sources in Srinagar said the bus was ripped apart in the massive explosion, turning it into a mangled mass of metal and on its side.
Witnesses said the blast shook the entire area, leading to disruption of traffic on the strategic highway that leads to the border areas in north Kashmir.
"The earth shook under my feet like a high intensity earthquake. We ran for safety," said a local resident.
No outfit has yet claimed responsibility for the blast.
The entire area was surrounded by army and paramilitary for searches. Senior army and police officers are already at the spot.
Saturday's terrorist strike comes after a long hiatus so far as its magnitude and toll is concerned.
Level of violence in Kashmir had fallen after a peace process between India and Pakistan started in 2004.
The blast comes close on the heels of the recent Sopore encounter, where a cop was killed and 13 securitymen were wounded. Two terrorists were also killed in 24-hour-long gun battle.