A troop of 120 soldiers was sent to Bule on Thursday, some five kilometres (three miles) from the hamlet of Katshelli where at least 65 people, among them 40 children, were shot and hacked to death on Monday.
“The mission is to secure the town of Bule and to prepare the ground for a larger, permanent deployment,” said UN spokesman Leocadio Salmeron in Bunia, the main town in the northeastern Ituri region.
This is the first time UN troops have deployed outside Bunia - where they recently replaced a French-led force under a mandate allowing them to open fire to stop attacks on civilians.
The UN mission in Congo plans further deployment of troops beyond beyond Bunia next week.
Clashes between militias linked to the Hema and Lendu tribes for control of the mineral-rich Ituri region have left more than 50,000 people dead and forced a further 500,000 to seek refuge elsewhere.
Representatives of armed militia groups met in Bunia on Monday to discuss disarming soldiers, a process that would run parallel to the UN deployment in the region.
“We have given them 10 days to provide information about the location and strength of their forces, so we can get them to regroup and disarm,” Colonel Laurent Banal, the UN commander for the Ituri province, said on Friday.
The violence in the northeast has hampered efforts to end Congo's wider war, in which more than three million people have died since 1998, largely through disease and starvation.