A top Indian minister has said the government would not share proof that "a very large number" of militants were killed in air strikes inside Pakistan this week, after doubts were raised there were any casualties in the attack that stoked tensions between the nuclear-armed rivals.

Hostilities escalated rapidly following a suicide car bombing on Feb 14 that killed at least 40 Indian paramilitary police in Indian-controlled Kashmir. India accuses Pakistan of harbouring the Jaish-e Mohammad Islamist group that claimed the bombing.

Indian warplanes carried out air strikes on Tuesday inside northeast Pakistan's Balakot on what New Delhi called militant camps. Islamabad denied any such camps existed, as did local villagers in the area when Reuters visited.

Some Indian opposition leaders have asked the government to share evidence of the strikes.

But India's Finance Minister Arun Jaitley, one of Prime Minister Narendra Modi's top lieutenants, said "no security agencies ever share operational details".

"It's a very irresponsible stand," Jaitley said at a conference organised by the India Today media group.

Modi yesterday ripped into the Congress, accusing the party of providing ammunition to Pakistan with its criticism of the government over the air. Contending that the Congress stance would only please Pakistan, he said, "They asked for evidence of the surgical strikes. Now, they ask for evidence of the strikes by the Air Forces".

"I want to know from the Congress and other parties why they are bent on destroying the morale of the armed forces. Why is the Congress giving speeches where enemies are benefitting? When we had to stand united against terror factories, 21 parties united for questioning us," he added.

Indian Air Force officials said earlier it was up to the political leaders to decide when and how to release evidence of the Balakot strike.

Jaitley dismissed suggestions that the rapid escalation in tensions with Pakistan had anything to do with India's domestic politics ahead of a general election due by May. Pollsters expect the ruling party to benefit from the nationalistic passion sweeping the country.

Meanwhile, another Union Minister SS Ahluwalia yesterday said that the aim of the Indian Air Force strike in Pakistan's Balakot was to send out the message that India is capable of hitting deep inside enemy lines and did not intend to inflict "any human casualty".

Ahluwalia said neither Prime Minister Narendra Modi nor any government spokesperson had given any figure on casualty of the IAF air strikes. Rather, it was the media and social media where the unconfirmed figures of terrorist killed were being circulated, he said.