* Residents of Abobo flee after days of clashes
* New fighting also reported in west of country
* Clashes mark escalation in post-election crisis
* Rebels say kill 80 pro-Gbagbo troops, no verification (Adds New Forces death toll statement)
By Tim Cocks and Ange Aboa
ABIDJAN, Feb 24 (Reuters) - Terrified residents fled a day of gun battles in an Abidjan neighbourhood on Thursday and fighting erupted in Ivory Coast’s west in an escalation of a post-poll power struggle that threatens to reignite civil war.
The spread of clashes in the world’s top cocoa grower comes amid faltering diplomatic efforts to resolve a dispute between incumbent president Laurent Gbagbo and rival Alassane Ouattara, internationally recognised as the winner of a November election.
More than 300 people have been killed since then, according to U.N. figures, and worsening security this week propelled cocoa futures to 30-year highs. Diplomats believe the numbers of dead to be way higher because Gbagbo’s forces rarely disclose casualties of their own or civilians they kill.
Fighting broke out overnight in the west of the country, near the frontline between the two factions, as well as on the border with Guinea and Liberia.
The New Forces rebels, who made a botched bid to oust Gbagbo in 2002, said in a statement they killed 80 pro-Gbagbo troops or militiamen in that battle, but this could not be verified. Gbagbo’s army spokesman said he could not immediately comment.
Gbagbo has defied calls to step down despite U.N.-certified election results showing that Ouattara won the Nov. 28 poll, which was meant to reunify the country but has instead re-opened bitter divisions from the 2002-3 civil war.
In Abidjan’s Abobo neighbourhood, hearing reports of pro-Gbagbo reinforcements going in, hundreds of residents with bags piled on their heads streamed out, after three days of fierce clashes between forces loyal to Gbagbo and Ouattara.
At 1930 GMT, residents said gunfire was still audible.
“We heard explosions and shots ... We were not able to sleep ... even when it stopped,” said Akissi Konan, a 36-year-old mother of three on the road, clutching her youngest child to a sweat-soaked T-shirt. “We wanted to flee but we were scared, we waited until the sun rose before leaving the house.”
People of all ages piled into vehicles leaving the pro-Ouattara neighbourhood, where houses and walls are peppered with small arms fire and, in places, destroyed by heavy weapons.
Ouattara is holed up in a hotel in another part of Abidjan protected by U.N. peacekeepers but the rebels who have backed him are believed to have bolstered their presence in the city, raising the stakes in a battle for the commercial capital.
“(The U.N.) thinks the clash (in the west) poses a risk of armed conflict restarting ... which would have serious consequences for the Ivorian people and even the sub-region,” said Hamadoun Toure, spokesman for the U.N. mission.
The economy has ground to a halt as sanctions bite and more than 80,000 people have fled their homes, half of them have crossed into neighbouring Liberia, the United Nations says.
Ouattara’s government spokesman Patrick Achi said residents of Abobo had grown sick of being targeted by pro-Gbagbo forces.
“This is a civil war,” he said. “These people were being killed and now they’ve organised themselves to resist.”
He denied claims by Gbagbo’s government that rebels from the north had moved into Abidjan, saying they were civilians who had seized weapons from Gbagbo forces, some of whom had defected.
African presidents mandated to resolve the conflict were in Ivory Coast this week and are due to meet again soon in Mauritania to discuss the crisis, but there is little optimism that they will be able to broker a deal.
While they were in town, up to 15 Gbagbo loyalists were in an ambush on Tuesday, military sources said.
The U.N.’s High Commissioner for Human Rights said on Wednesday that there had been “a continuous pattern of serious human rights violations” since the election. New York-based Human Rights Watch also called for African action.
“These leaders need to step in to find a just and accountable way out of this stand-off before the violence gets any worse,” said Daniel Bekele, HRW’s Africa director.
“It is not calm. The army’s armoured vehicles and soldiers are heading towards the railway and PK 18 (an area in Abobo),” said resident Tiemoko Souala, who heard “sporadic gunfire”.
West African body ECOWAS, which has been stronger in its support for Ouattara than other parts of Africa, has threatened to force Gbagbo out, but any such operation is seen as far off.
Nigeria’s foreign minister told Reuters on Thursday that any intervention must be U.N. led and would more likely be an aerial and naval blockade than ground invasion. (Additional reporting by Loucoumane Coulibaly in Abidjan and Charles Bamba in Bouake; Writing by David Lewis)