"The Secretary-General emphasizes that attacks on civilians are unacceptable under all circumstances", says Stephane Dujarric, spokesperson for UN Secretary-General Antonio Guterres, in a statement.
Dozens of people are reported to have been injured, many of them seriously. The attack took place in the popular tourist resort of Pahalgam and is described as the worst in a long time.
"The attack is much larger than anything we've seen targeting civilians in recent years", says Omar Abdullah, a high-ranking politician in the region of Jammu and Kashmir, in a statement.
Four shooters
According to police reports, there were four shooters described as militiamen. No group has claimed responsibility for the attack.
"Their evil agenda will never succeed. Our determination to combat terrorism is unwavering and will only be strengthened", says Prime Minister Narendra Modi, who has cut short a visit to Saudi Arabia due to the incident, in a statement.
US President Donald Trump has spoken by phone with Modi and "condemned the terrorist attack and expressed his full support to India", according to India's Foreign Ministry.
EU Commission President Ursula von der Leyen also condemns the attack and says on X that "Europe stands together" with India.
India's Home Minister Amit Shah promises "the strictest consequences" for the perpetrators.
"Those involved in this brutal terrorist attack will not be spared", he says in a statement.
Nuclear powers India and Pakistan control each their part of the scenic mountain region of Kashmir, but both claim the entire area. Since 1989, mainly Muslim rebel groups have fought against Indian rule.
In 2019, Narendra Modi's government decided to revoke Kashmir's special status with self-governance, aiming to make the region a state.
The worst attack in recent years occurred in Pulwama in February 2019, when a car loaded with explosives rammed into police cars and killed 40 people. The deadliest attack with civilian victims in recent years took place in March 2000, when 36 people were killed.