At least 40 Indian paramilitary soldiers have been killed in a bomb attack by militants on their convoy in India-administered Kashmir.
Local media reports said that a car carrying between 300kg and 350kg of explosives rammed a bus that was carrying roughly 2500 troops to the main city in Indian-administered Kashmir, Srinagar, in a convoy of about 70 vehicles at 3.15pm.
The blast took place on the heavily guarded Srinagar-Jammu highway about 20km from the city, which reports said had been closed for a week because of snow.
Pakistan-based Islamist group Jaish-e Mohammad said it was behind the attack.
"A car overtook the convoy and rammed into a bus with 44 personnel on board," a senior police official told BBC.
The official said the death toll might increase because dozens were "critically injured".
It is the deadliest militant attack on Indian forces in Kashmir since the insurgency against Indian rule began in 1989.
Indian Prime Minister Narendra Modi condemned the attack, describing it as "despicable".
Attack on CRPF personnel in Pulwama is despicable. I strongly condemn this dastardly attack. The sacrifices of our brave security personnel shall not go in vain. The entire nation stands shoulder to shoulder with the families of the brave martyrs. May the injured recover quickly.— Narendra Modi (@narendramodi) February 14, 2019
Home Minister Rajnath Singh said Jaish-e-Mohammad was "Pakistan-based and Pakistan-backed" while Finance Minister Arun Jaitley said those responsible would be given an "unforgettable lesson for their heinous act".
The latest attack follows a spike in violence in Kashmir that came about after Indian forces killed a popular militant, 22-year-old Burhan Wani, in 2016.
More than 500 people were killed in 2018 - including civilians, security forces and militants - the highest such toll in a decade.
However, there have been several attacks targeting Indian troops in the region since 1989.
Before Thursday's blast, the deadliest attack on Indian security forces in Kashmir this century came in 2002 when militants killed at least 31 people at an army base in Kaluchak, most of them civilians and relatives of soldiers.
More recently at least 19 Indian soldiers were killed when militants stormed a base in Uri in 2016. Delhi blamed that attack on the Pakistani state, which denied any involvement.
Bashir Manzar, a journalist based in Indian-administered Kashmir, said the bombing would boost the morale of militants and contradicted claims the situation in Kashmir was being brought under control.
"Over the past few months, political leaders in Srinagar and Delhi have made tall claims about how the situation in Kashmir has been normalised and hundreds of militants, including top leaders, had been killed," he said.
"They claimed that militant groups were on the defensive and fewer people were joining their ranks."
The two countries have fought three wars and a limited conflict since independence from Britain in 1947 - all but one were over Kashmir.
Started by cleric Maulana Masood Azhar in 2000, Jaish-e-Mohammad has been blamed for attacks on Indian soil in the past, including one in 2001 on the parliament in Delhi which took India and Pakistan to the brink of war.
It is also said to have introduced suicide bombings in Kashmir, with the first such attack taking place in 2000.
It has been designated a "terrorist" organisation by India, the UK, US and UN and has been banned in Pakistan since 2002.
However Maulana Masood Azhar remains at large and is reportedly based in the Bahawalpur area in Pakistan's Punjab province.
India has often demanded Maulana Masood Azhar's extradition from Pakistan but Islamabad has refused, citing a lack of proof.