The Indian army reportedly attacked separatist rebels along the border with Myanmar on Tuesday, though it is not clear whether this was indeed a cross-border strike.

The surgical strike on two camps of militants was carried out in retaliation for the killing of 20 soldiers in an ambush in Manipur last week, the heaviest losses for security forces in Manipur in two decades.

The government said its tough response showed its resolve to fight terrorism beyond the country's borders. But on Wednesday Myanmar maintained that its border was not crossed and that Indian forces had attacked insurgents inside India.

In a Facebook post, Zaw Htay, director of Myanmar’s presidential office, said, “According to the information sent by Tatmadaw (Myanmar army) battalions on the ground, we have learned that the military operation was performed on the Indian side at India-Myanmar border.”

He also said Myanmar would not tolerate rebel groups using its soil to attack neighbours.

Both India and Myanmar have cooperated in the past against militants using havens in Myanmar. According to military experts, it is likely that the Indian government kept its Myanmar counterparts in the loop before the retaliatory attacks took place, even if these were within Indian territory.

According to Reuters, the northeast which borders China, Bhutan, Bangladesh and Myanmar, is home to dozens of insurgent groups fighting for autonomy or secession from India.

Despite militants allegedly having sanctuaries in Myanmar, Bangladesh and Bhutan, Indian soldiers have very rarely crossed borders to attack rebel camps.

The army said in a statement that its soldiers inflicted "significant casualties" but gave not details. According to Times of India, the attack reportedly lasted for about 45 minutes, leaving over 100 militants dead.

The army did not say soldiers had crossed the border but the government did.

Minister of state for information and broadcasting Rajyavardhan Singh Rathore told NDTV that the government had taken the bold step to strike at militant camps and he congratulated Prime Minister Narendra Modi for doing so.

He also said it was a signal to neighbours that India would not tolerate militant attacks from across its borders.

"It is undoubtedly a message to all nations that harbour any intentions - be it the west or the specific country we went into right now. Even if there are groups within countries that harbour terror intentions, we will choose the time and the place of hitting them."

In response, Pakistan’s interior minister Chaudhry Nisar Ali Khan said India should not mistake Pakistan for Myanmar.

“The Pakistan Army is fully capable of responding to any adventurism,” he declared on Wednesday.

- Karan Singh 

To Learn More:

Myanmar says operation on militants was on Indian side of border (AFP)

Inside story: Over 100 northeast militants may have been killed in Army's Myanmar operations (by Bharti Jain, Times of India)

Indian army hunts militants in Myanmar in rare cross border strike (by Sanjeev Miglani, Reuters)

Myanmar strike: Not the first time Army conducted cross-border operations (by Sushant Singh, Indian Express)

As India conducts strikes in Myanmar, Pakistan cautions against cross-border 'adventurism' (Hindustan Times)