A Mizoram police spokesman said paramilitary commandos launched Operation Hailstorm on the main base of the Chin National Army (CNA) near Mohre village, about 400 km south of the state capital Aizawl. The operation began June 17.

"The moment the operation was launched, CNA militants began fleeing to Myanmar in batches and by the time our troopers zeroed in on their regular camp, we found all of them escaping to the other side of the border," Mizoram police chief Lalngheta told IANS.

"We believe there were about 200 rebels sheltered in that camp."

The CNA is the armed wing of the Chin National Force (CNF) founded in 1988 against the military-run Myanmarese government and for more autonomy for various ethnic minority groups in that country.

Many young Chin tribal youths from Myanmar entered India during the height of the pro-democracy uprising and later joined the CNF.

"The CNA rebels were involved in collecting tax from local people in Mizoram although they did not indulge in killings or kidnappings," the police chief said.

The area leading to the camp is heavily mined, with explosive experts and landmine sweepers now engaged in clearing the location.

"We believe up to 2,500 landmines planted all over their camp which they called Victoria," Lalngheta said. Police and intelligence officials say the Myanmarese rebels had set up the camp at least a year ago and were taking advantage of the fact that the area was remote and unguarded and close to the international border.

India and Myanmar share a 1,640-km long unfenced border, of which 350 km lies along Mizoram.

"We have intensified security patrol in the border areas to prevent militants from Myanmar from entering the state once again," the police chief said.

In December, an army captain was killed in a raid inside Mizoram by Myanmarese guerrillas belonging to the newly formed Chin International Army (CIA).

Several ethnic rebel groups from Myanmar have in the past made forays into parts of Mizoram for either carrying out extortion or for trafficking drugs, taking advantage of the rugged mountainous terrain along the border.

"We suspect groups like the CIA could be involved in drug trafficking as well," another police official said.

At least five frontline anti-India rebel armies operating in the country's northeast have bases in northern Myanmar from where they carry out their hit-and-run guerrilla strikes on troops in the region.

India's porous and mountainous northeastern frontiers, bordering Myanmar and Bangladesh, have become one of the world's busiest small arms' bazaars, feeding insurgencies and rebellions across South Asia.

"The unfenced border area has always been a hot favourite with gunrunners. Illegal arms consignments reach the northeast via Bangladesh and Myanmar at frequent intervals," Mizoram Chief Minister Zoramthanga said.

"The only way to check the flow of illegal arms reaching the hands of underground outfits is to fence the international borders and intensify security in the area."

The chief minister was himself a top militant leader of the outlawed Mizo National Front before the outfit surrendered in 1986 and entered the political mainstream.

Most of the weapons, including AK-47 and AK-56 assault rifles, mortars, 40 mm rocket launchers, pistols, revolvers and grenades, come via the Arakans - a mountainous area in Myanmar - from parts of Thailand and Cambodia.