A battalion of 780 Nigerian soldiers arrived Tuesday in the northern town of Makeni, headquarters of the rebel Revolutionary United Front, said U.N. spokeswoman Margarette Novicki.
Another 780 Bangladeshi troops arrived about the same time at Magburaka, also in the north, she said.
A third contingent of about 500 Zambian troops had deployed overnight at Mano Junction, a strategic crossroads on the road to the West African nation's diamond fields in the east, U.N. officials said.
The deployments are part of a broader move that began last month to consolidate the government's control over the country and secure a fragile peace deal reached in Abuja, Nigeria, last November.
All the latest deployments are in areas controlled by the rebels. So far, they have taken place without incident.
Similar deployments were made last May when the U.N. began moving into rebel territories to disarm dissidents and help enforce a 1999 peace agreement. But rebels responded by taking 500 U.N. troops hostage, seizing U.N. vehicles and restarting the war.
"I am very positive that any attempt to touch or take any peacekeepers who are on the move right now I am promising that you will have a bloody nose," said acting U.N. force commander, Nigerian Maj. Gen. Martin Luther Agwai.
"We can meet any security threat," he said.
Led by Foday Sankoh, who is now jailed, the rebel movement made mutilation its trademark. Largely uneducated, rural recruits had killed and maimed tens of thousands of civilians since the insurgency began in neighboring Liberia in 1991.
Agwai said the U.N.'s latest deployments had taken place after preliminary long-range patrols had visited each of the three towns.
Soldiers left for Makeni and Magburaka in a 200-vehicle convoy of trucks and armored personnel carriers, he said.
Information Minister Julius Spencer said the government was "very pleased" the deployments were going ahead and expected more in the future.
Elsewhere in the country, U.N. workers announced plans to move some 80,000 Sierra Leonean refugees who've taken refuge in a Guinea border area to camps in interior sections of the country. Fighting near the border region has cut the refugees off from aid.
Kris Janowski of the UN High Commissioner for Refugees said in a statement that "several thousand refugees" have already "walked back to government-controlled areas in Sierra Leone, passing through dangerous border zones in a desperate attempt to flee tensions in the Parrot's Beak."
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