Ivory Coast's new army turned its guns on a former ally who helped install the democratically elected president but failed on Thursday to defeat the renegade forces who are dug into a neighborhood of Abidjan, military sources said.
Infighting among forces who recognize President Alassane Ouattara also erupted Wednesday in the southwestern cocoa port of San Pedro, the sources said.
Rockets and mortars were fired in both places, with civilians trying to flee the crossfire.
The violence presents a major setback for the country, which was taking timid steps toward normality following the April 11 arrest of strongman President Laurent Gbagbo.
The shooting in San Pedro started when one group of soldiers tried to stop another from looting, one source said. U.N. peacekeepers intervened to stop the combat after the fighters started launching mortars and rockets in downtown San Pedro, said the officer, who spoke on condition of anonymity because he was not authorized to speak to reporters.
Residents said heavy machine-gun fire rocked Abidjan's working-class suburb of Abobo about 5 p.m. (1700 GMT) Wednesday near renegade warlord Ibrahim "IB" Coulibaly's headquarters. Residents scattered and ran to lock themselves into their homes. Coulibaly orchestrated two failed coup attempts in 1999 and 2002.
Abobo saw some of the worst fighting during the four-month political standoff created by Gbagbo's refusal to cede power to Ouattara after a November election.
Four military sources from both sides confirmed that the new army of former rebels led by Prime Minister Guillaume Soro, who also is Ivory Coast's defense minister, attacked Coulibaly's headquarters but were met with fierce resistance that lasted more than an hour. Coulibaly and Soro are longtime rivals.
A fighter in Coulibaly's forces who uses the nom-de-guerre Capt. Meyo Aka told The Associated Press that they drove government troops back and they finally left.
He blamed Soro for the conflict, claiming Soro is intent on remaining prime minister and "needs to create insecurity to justify retaining the portfolio."
Ouattara is expected to imminently announce a new Cabinet and had made an election campaign promise to give the premiership to the party of his electoral ally Henri Konan Bedie.
It was not possible to get comment from Ouattara or Soro on Thursday despite visits to the seat of government that is operating temporarily out of the Golf Hotel.
U.N. spokesman Hamadoun Toure confirmed fighting in the two Abidjan suburbs and in the port city. He said mortars and rockets were used.
Coulibaly on Sunday pledged allegiance to Ouattara during an AP interview, saying he regards as a father the man whose wife he protected as head of her bodyguard corps from 1990 to 1993 when he was an army chief sergeant and Ouattara was prime minister.
Toure, the U.N. spokesman, said the U.N. is talking to the army and to Coulibaly's forces.
"We are trying to see how to help," he said. "To defuse tension, we're talking to the two parties to see how we can very, very swiftly find a resolution to this conflict because it will jeopardize all the efforts made over the past four months to ensure the security of the population."
He said the U.N. mission had emphasized to both sides that it has a mandate to destroy heavy weapons that are used against the population.
"We're using all our efforts, politically speaking, in a diplomatic way, but we also have other means according to our mandate and we have told the parties we will not tolerate the use of heavy weapons against civilians."
Analyst Richard Moncrieff of the South African Institute for International Affairs said Ouattara does not have command and control over the troops who entered Abidjan to force Gbagbo from the presidency.
"This could have serious repercussions for what is to come," Moncrieff said.
Also on Thursday, the African Union dropped its sanctions against Ivory Coast. The AU, which endorsed Ouattara's electoral victory, had imposed the sanctions to target Gbagbo, whose refusal to step down propelled the country into chaos.
The AU also urged Ouattara to start the peace-building process as soon as possible and to reconcile his people.
Gbagbo lost November elections but refused to accept defeat. He is currently under arrest and faces possible trials. Toure said he remains under U.N. protection.
A million people have fled the capital of about 5 million and another million are displaced in the country or have fled to neighboring states. Thousands have been killed and wounded.
The city of Abidjan, meanwhile, showed some signs of returning to normal. Fewer roadblocks were seen Thursday, and there were fewer fighters careening around on looted vehicles with removed license plates and torn-off doors. A bulldozer on the highway collected mountains of garbage.
But despite calls from Ouattara for people to return to work and for businesses to open, in Abidjan's downtown business center of Plateau, most shops remained shuttered with metal grills over their doors and windows. Some people were cleaning up, sweeping shattered glass of shop windows.
Banks haven't opened because many have been pillaged. Outside the Abidjan branch of the regional bank stood a U.N. tank and armored personnel carrier.
Associated Press writer Luc Van Kemenade contributed to this report from Addis Ababa, Ethiopia.