New Delhi: Just two days after the Indian Army carried out a covert operation inside Myanmar to neutralise militants, the Government has sounded a high alert across North-East.

According to sources, NSCN-K militants have entered the country for a ‘revenge attack’.

Earlier on Tuesday, the Union government minister — in a highly controversial move — officially “confirmed” that Army troops did enter Myanmar to attack militants based there.

Read: We’re no Myanmar: Pakistan Minister to India

Defence sources said more such cross-border anti-terror attacks by the Army on militants based in Myanmar are not ruled out in future, adding that the rebels are likely to shift base from their current locations following Tuesday’s assault.

While one government minister on Tuesday night, in a clear hint at Pakistan, said the cross-border raid is undoubtedly a message to all nations that harbour any terror intentions, be it the western frontier or elsewhere, and that “even if there are groups within a country that harbour terror intentions, we will choose the time and place of hitting them”, another government minister on Wednesday said “this (the Myanmar raid) is a lesson and a message to all the terror groups that India will not hesitate in going beyond its geographical borders to eliminate terrorists”.

Read: Indian Army's Myanmar operation a message to other neighbours, says Union Minister

Amid fears that the Indian government’s confirmation of the cross-border raid could have ended up upsetting and embarrassing the Myanmar Army and government globally, Myanmar on Wednesday denied that Indian forces had attacked insurgents in its territory but added it would not tolerate rebel groups using its soil to attack neighbours.

According to reports, the raid was carried out by a crack team of about 70 commandos of the Indian Army who finished the operation within 40 minutes.

Commandos of 21 Para (Army Special Forces), equipped with assault rifles, rocket launchers, grenades and night-vision goggles, were airdropped for the operation just inside Indian territory, near the border with Myanmar.

Read: Myanmar denies Indian Army raid inside its territory

Once on the ground, the contingent split into two groups and headed for two militant camps, being run by the NSCN (K) and KYKL.

The teams trekked through the thick jungles for at least five km before they reached the militants’ training camps and destroyed them, the reports said.

Indian defence sources, meanwhile, sounded a word of caution, saying any extension of the cross-border strategy to Pakistan-occupied Kashmir would be a totally different ball-game since Pakistan is a nuclear-armed nation and the Pakistan Army is also active on the LoC.

Defence sources said at least 20 militants were killed in Tuesday’s cross-border raid while 11 others had been seriously injured. But some news agency reports put the death toll of militants higher, at about 38.

Read: Jitendra Singh rushes to Manipur to take stock of situation

The plan to carry out surgical strikes against the Northeast militants involved in the killing of 18 Army personnel in Manipur last week was initially discussed at a meeting chaired by Union home minister Rajnath Singh on June 4 and attended by defence minister Manohar Parrikar, NSA Ajit Doval, Army Chief Gen. Dalbir Singh Suhag and top security and intelligence officials.

The exact details of the plan were subsequently finalised at a meeting of NSA Doval and the Army Chief after he returned from his Manipur visit.

According to sources, after the plan was finalised, the NSA took final approval from Prime Minister Narendra Modi following his return from Bangladesh on the night of June 7.

Read: Congress slams ministers' ‘boastful and jingoistic’ remarks on Army operation in Myanmar

According to some reports, there were nearly 150 Naga and Meitei militants present in the first camp when the Army’s anti-terror strike began, while nearly 50 militants were present in the second camp when Army commandos reached there. There were also some reports that claimed that NSCN (K) chief and militant leader S.S. Khaplang managed to escape though he was present in the area in Myanmar when the Army operation was launched.