The failure on Thursday comes as a sign of difficulties ahead for a new peacekeeping force in the war-battered African nation.
Bangladeshi and Pakistani UN troops took over this week from a French-led mission to the main town of Bunia in the Ituri region, which is roughly the size of Ireland, to protect civilians from ethnic militia.
Under the UN force's new mandate it can deploy beyond Bunia's borders to the rest of the towns in Ituri region where rival militias still kill, loot and rape with impunity. The force can use firepower in pursuit of its mission.
Forced to flee
UN helicopter missions have already flown over Fataki, 70 km northeast of Bunia, without landing, reporting it to be largely abandoned after what residents describe as attacks by militia that have forced thousands to flee.
The military contingent of the mission approached Fataki by helicopter but were forced to leave several minutes after landing, when heavy rain began falling.
"Attacks are coming, how will people manage without the UN? How will we ever take our towns back?"
Refugee from Fataki
"They didn't know what they would find on the ground, and if the storm continued and they ended up being blocked there, it would be dangerous," said one UN official in Bunia.
"The UN need to secure Fataki and Bule soon," said Rogeline Lotsove, a young woman in Bunia, who fled Fataki three weeks ago. "Attacks are coming, how will people manage without the UN? How will we ever take our towns back?"
Violence in Bunia
Attacks by the Hema and Lendu militia in Bunia and the mineral rich Ituri have claimed more than 50,000 lives and forced half a million people to flee since 1999.
The UN presence has not completely halted the ethnic violence even in Bunia, where Hema residents of the Chem Chem district said Lendu attackers had rushed out of a local chief's house and chased civilians away, killing one.
"They pillaged the area but they fled when they were spotted by UN armed vehicles," said Babona Moizi, 31, a student.
A UN military spokesman confirmed that a man, apparently a Hema, had been killed by three Lendu men. Residents said at least four other people were still missing.