Calling it despicable, Modi said "the sacrifices of our brave security personnel won't go in vain'."
"The entire nation stands shoulder to shoulder with the families of the brave martyrs. May the injured recover quickly," he said in a tweet.
In his accompanying tweet, Modi said he spoke to Home Minister Rajnath Singh and other top officials regarding the situation.
At least 30 CRPF personnel were killed in the deadly attack when a Jaish-e-Mohammed terrorist rammed an explosives-laden vehicle into the bus they were travelling in. The attack is seen as one of the worst terror strikes in the state in recent years. The Congress party on Thursday criticised the Modi government for its inefficiency in restricting terror attacks in the country and said this was the 17th biggest terror attack in the last five years.
More than 2,500 Central Reserve Police Force personnel, many of them returning from leave to rejoin duty in the Valley, were travelling in the convoy of 78 vehicles when they were ambushed on the Srinagar-Jammu highway at Latoomode in Awantipora, reported PTI.
Police said the terrorist driving the suicide vehicle was Adil Ahmad from Kakapora in Pulwama who joined the JeM in 2018.
The casualties are likely to go up.