General N.C. Vij said separatists fighting in northeastern India were still operating in neighbouring Bangladesh and Myanmar after losing most of their bases in Bhutan.

"We have sent our troops to train Myanmarese forces and we might well come up to that stage for joint operations," Vij said in Guwahati, the capital of the revolt-ridden state of Assam, after a visit to the Bhutan border.

"Myanmar and Bangladesh are still safe havens for the militants, but the presence of militants is comparatively higher in Bangladesh than in Myanmar," Vij told reporters.

Vij is the latest Indian official to allege a rebel presence in Bangladesh, which denies any extremists operate from its territory.

Bhutan, at the urging of New Delhi, on December 15 launched its first military operation in modern times to oust three rebel groups that had carried out hit-and-run attacks on Indian targets from bases in the Buddhist kingdom.

Vij said 650 rebels had been killed or taken into custody. He did not break down the figure.

The Indian army, which is backing the operation, had earlier reported the deaths of 141 rebels and eight Bhutanese troops and support personnel since the offensive started.

Bhutan has not released casualty figures but said its forces have destroyed all 30 camps run by the militants.

Vij, however, said rebels still controlled two bases.

"Militants are still holding on to two of their camps and fighting is still going on there," he said. "But very soon they will be neutralised."

The rebel strength was estimated at 3,000 before the operation began. More than 10,000 people have died in separatist violence in Assam since the 1980s.

India has in recent years been building ties with Myanmar, partly to counter what it perceives as growing Chinese influence on its neighbour.

Ties were strained after the military took power in Yangon in 1988 and India granted sanctuary to exiles.

The military campaign by Indian ally Bhutan came ahead of a seven-nation South Asian summit that will start Sunday in Islamabad.

Indian Foreign Minister Yashwant Sinha said Thursday that the Bhutanese campaign was "an example worth emulating by all those countries where terrorism takes shelter."

Bangladeshi troops later Thursday arrested six armed Indian nationals in the Habiganj district.