Two people were killed and several others injured after UN peacekeepers opened fire during an incident in the eastern Democratic Republic of Congo on the Uganda border on Sunday.
The UN force MONUSCO, admitted that some of its peacekeepers had opened fire "for unexplained reasons", adding that arrests had already been made.
Video of the incident, shared on social media showed men, at least one in police uniform and another in army uniform, advancing towards the immobilised UN convoy behind a closed barrier in Kasindi. The town is in eastern DR Congo's Beni territory on the border with Uganda.
After a verbal exchange, the peacekeepers appeared to open fire before opening the barrier and driving through while people scattered or hid.
"During this incident, soldiers from the intervention brigade of the MONUSCO force returning from leave opened fire at the border post for unexplained reasons and forced their way through," the UN mission in Kasindi said in a statement. "This serious incident caused loss of life and serious injuries."
"The toll is two dead," Joel Kitausa, a civil society leader in Kasindi, told AFP, adding that 14 people were injured in the incident.
'Shocked and dismayed'
The UN envoy in the Democratic Republic of Congo, Bintou Keita, said she was "deeply shocked and dismayed by this serious incident", according to the mission's statement.
"In the face of this unspeakable and irresponsible behaviour, the perpetrators of the shooting have been identified and arrested pending the conclusions of the investigation which has already begun in collaboration with the Congolese authorities," MONUSCO said.
The UN mission said the troops' home countries had been contacted so legal action could be commenced promptly, with the involvement of witnesses and survivors, which could lead to exemplary penalties.
Earlier Barthelemy Kambale Siva, the North Kivu governor's representative in Kasindi, said that "eight people, including two policemen who were working at the barrier, were seriously injured" in the incident.
Kambale Siva, interviewed by AFP, did not give a reason for why the UN convoy was prevented from crossing.
There are more than 120 militias operating in the DRC's troubled east. The UN first deployed an observer mission to the region in 1999.
In 2010, it became the peacekeeping mission MONUSCO -- the United Nations Organization Stabilization Mission in the Democratic Republic of the Congo -- with a mandate to conduct offensive operations.
There have been 230 fatalities among the force, according to the UN.
Calls for UN forces to leave
Last week, deadly demonstrations demanding the departure of the United Nations took place in several towns in eastern DRC.
A total of 19 people, including three peacekeepers, were killed.
Anger has been fuelled by perceptions that MONUSCO is failing to do enough to stop attacks by the armed groups.
UN under-secretary-general for peace operations Jean-Pierre Lacroix was in the central African country on Saturday to "talk to the Congolese authorities", he said.
"(They would) examine ways in which we can both avoid a recurrence of these tragic incidents and, above all, work better together to achieve our objectives," he said.
"We hope that the conditions will be met, in particular the return of state authority, so that MONUSCO can complete its mission as soon as possible. And to leave room for other forms of international support."