Students loyal to the Ivorian leader who is refusing to cede power attacked a U.N. vehicle in the country’s main city on Thursday, setting it ablaze and beating its driver.

A witness who declined to be identified for security reasons said supporters of Laurent Gbagbo - who has called for the U.N. peacekeeping force here to leave the country - set up a makeshift roadblock in the Riviera II neighbourhood and forced the vehicle to stop. They dragged the driver out of the four-wheel drive car and beat him while another group smashed the vehicles windows and set it on fire, he said. Riviera II is a Gbagbo stronghold.

It was not immediately known what happened to the driver, and the United Nations mission in Abidjan said it was looking into the attack and could not yet comment.

The cocoa-producing country has been tense since a heavily disputed November 28 election which the international community says opposition leader Alassane Ouattara won. Mr. Gbagbo, who refuses to give up power, still controls the military and security forces across this lagoon-side city.

An Associated Press reporter who arrived on the scene after the attack saw the vehicle still smouldering. There were no U.N. troops or security forces in sight.

The witness said the students also tried to stop a U.N. truck that drove by shortly afterward. The truck escaped, but the students grabbed a bag filled with what appeared to be U.N. peacekeeping uniforms, which some of them put on.

Late Wednesday, army chief Philippe Mangou warned that his troops reserve the right to retaliate following two days of deadly clashes in an opposition stronghold neighbourhood of Abobo, raising concerns about more violence amid the nation’s simmering political crisis.

Authorities have imposed a curfew in Abobo and sent in a convoy of military trucks following the clashes that began on Tuesday after a police raid. At least four civilians and as many as seven police officers have been killed in the unrest.

“In order to find these people attacking the republic inside their hiding places, the armed forces of Ivory Coast want all human rights organizations, as well as the national and international community to know that that these attacks against us are equal to acts of war ... putting us in a position of legitimate self-defense,” Mr. Mangou said in a declaration read on state TV on Wednesday.

U.N. Secretary-General Ban Ki-moon has expressed deep concern about the violence in Abobo, and U.N. spokesman Martin Nesirky said that Mr. Ban urged both sides “to exercise maximum restraint and to avoid further clashes.”

Mr. Gbagbo lost the election by a nearly nine-point margin according to results certified by the United Nations. A peace agreement after the country’s 2002-2003 civil war invited the U.N. to act as the final arbiter of the election, creating an independent mechanism for determining the outcome.

Elections in Zimbabwe and Kenya in recent years have ended with the opposition candidate forced to accept a power-sharing agreement with the sitting president, even though most observers say the opposition had won in both instances.

Country experts warn that Mr. Gbagbo is likely hoping for a similar arrangement and is using the tool of human rights abuses, including the military crackdown, as a way to raise the stakes.

Africa expert Jennifer Cooke of the Centre for Strategic and International Studies in Washington said there is a strong aversion from both African and Western leaders to reinforce the precedent of “government by negotiation.”

“The idea that an incumbent who loses an election need only hang on and threaten violence in order to obtain a power-sharing deal,” she argues, “is a dangerous blow to democracy in a continent that will see some 15 national elections in the coming year.”

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