Police fired tear gas to disperse protesters who hurled stones at a UN peacekeepers' convoy in the volatile east of the Democratic Republic of Congo Friday, one of several small demonstrations demanding an extension of the security zone.
Local residents targeted the UN convoy near the airport in the provincial capital Goma, forcing the closing of shops in the area after the police intervention, a local leader Jean-Mobert N'senga said.
Also a group on motorcycles had driven around the city, honking and shouting, "we are chasing MONUSCO," as the UN mission in DR Congo is known, an AFP photographer reported.
Protesters are angry that a new UN security zone will not take in the regions under the control of the rebel M23 movement, which briefly controlled Goma in November. And on July 14, when fighting resumed between the Congolese army and the M23, the rebels' shelling hit the city.
N'senga's Fight for Change (Lucha) youth movement issued a statement demanding "the immediate extension of the security zone... in order to secure thousands of other civilians who are in zones under the occupation of the M23 and other armed groups."
On Thursday UN peacekeepers began patrolling a new security zone in the Goma-Sake region, which has about a million residents, and includes dozens of roving militias.
The security zone was established after MONUSCO on Tuesday gave a 48-hour deadline to armed groups and individuals to surrender or risk being disarmed by force.
As the deadline came and went it was not clear how many fighters had heeded the call, which the M23 had dismissed as irrelevant.
The United Nations gave no immediate indication that military action had started or was planned in the troubled region which holds massive potential mineral wealth for a country that is almost as big as western Europe.
But protesters claimed that security zone was not enough.
"It is absurd to claim to protect the civilian population 'in densely populated Goma and Sake' without protecting the sources of food supplies which are currently in the regions plagued by armed groups" in Nord Kivu province, the Lucha statement said.
The group also accused the M23 rebels in recent weeks of looting, kidnapping and other attacks on civilians.
On Thursday, the commander of the UN force, Brazilian general Carlos Alberto Dos Santos Cruz said that the parameters of the security zone were not fixed.
"This is only a first step. Each zone has its own particular conditions. We are going to adapt to the situation on the ground," he said.
The DR Congo has been wracked by violence and civil war since independence from Belgium in 1960, often fuelled by its vast mineral wealth and drawing in its neighbours, particularly in the eastern provinces.