A raid by India's army on insurgents accused of killing 18 Indian soldiers last week took place on Indian soil, not inside Myanmar as some Indian media reported, a Myanmar official said Thursday.

Although Myanmar has relatively little control over the porous border region, it would be loath to acknowledge an intrusion by its bigger neighbor, and public claims by some Indian officials to that effect would be an embarrassment that could chill bilateral relations.

The incident has cast rare light on the insecurity along the two nations' 1,600-kilometer (1,000-mile) border, whose remoteness provides shelter to insurgent groups in India's restive northeast.

The disputed raids took place shortly before Indian national security adviser Ajit Doval is to visit Myanmar to discuss security affairs and insurgency issues along the border. India has long worked to keep strong ties with Myanmar's government, in part so that rebel militias do not find safe havens there.

Comments by Indian officials have been vague or contradictory about where Tuesday's raids against the insurgents took place. A junior information minister, Rajyavardhan Singh Rathore, said the Indian troops crossed the border into Myanmar with the acquiescence of its government.

However, Myanmar President's Office director Zaw Htay said Thursday the raids occurred inside India and that foreign rebels are not allowed to operate on Myanmar soil.

The claim that Indian troops attacked inside Myanmar's territory has triggered criticism from some Indian politicians, who treated the report as true but suggested that publicly announcing it was boastful and diplomatically indiscreet. On Thursday, Indian Defense Minister Manohar Parrikar declined to comment on details of the attack.

Myriad militant groups in India's remote northeast have been fighting the central government for decades, some of them rooted in Myanmar and operating from both sides. The groups, ranging from ragtag collections of barely equipped young men to small armies with hundreds of heavily armed guerrillas, are fighting for a range of issues including political independence and control of drug routes.

Zaw Htay said Myanmar's army confirmed that India's raids were carried out in its own territory, and that India's ambassador provided Myanmar's deputy foreign minister with the same account.

A top Indian army officer, Maj. Gen. Ranbir Singh, said Tuesday the army was in communication with Myanmar authorities on its operation and inflicted "significant casualties on the rebels."

While most clashes with the militants are minor, last week's attack on an Indian army convoy in Manipur state shocked New Delhi.

The state has several active militant groups which operate from both sides of the border. None claimed responsibility for the attack, which also wounded 14 soldiers.

In April, insurgents armed with automatic weapons fired at two trucks carrying Indian paramilitary soldiers in neighboring Nagaland state, killing eight of them.

Most of the main rebel groups in Manipur state are not engaged in cease-fire talks with the Indian government, unlike those in other remote northeastern states.

Separatist groups accuse the Indian government of exploiting the region's rich natural resources while neglecting local development.