By Ange Aboa and Loucoumane Coulibaly
ABIDJAN (Reuters) - Former rebels controlling the north of Ivory Coast opened up two new fronts on Monday, and heavy clashes broke out in a western cocoa-producing area as a bid to force incumbent Laurent Gbagbo from power escalated.
Rebels who seized the north in the 2002-3 civil war and now back Alassane Ouattara, Gbagbo's rival and the man recognized as president by most world leaders, on Monday advanced on Duekoue, which had previously remained under Gbagbo's control.
Ouattara's men said they had taken Duekoue, sited on a main road in a region that produces around 250,000 tones of cocoa a year for the world's top growing nation. But Gbagbo's forces denied it and several witnesses said fighting was continuing.
A dispute over last November's presidential election, which was meant to draw a line under Ivory Coast's civil war, has instead restarted it after Gbagbo refused to step down despite U.N.-certified results showing that he lost.
The rebels also opened up two fresh military fronts in the east and west, in an apparent escalation of their push after fighting had been limited to Abidjan and the far west.
Witnesses said Ouattara's forces had seized a major eastern town, Bondoukou, after advancing on it from the north.
"The rebels are in the town and they are moving all around the place in vehicles. They are shooting. Everyone has gone inside," said resident Dramane Yao, a driver.
A military source said pro-Gbagbo forces still retained some "strategic points" within the town.
Another military source said rebels had also marched south to an area just outside Daloa, in the heart of Ivory Coast's cocoa belt, but had not yet met resistance from Gbagbo's forces.
Up to one million Ivorians have now fled fighting in the main city Abidjan alone. Others have been uprooted across the country and around 100,000 have crossed into Liberia, to the west, according to the U.N. refugee agency.
Although internationally recognized as president, Ouattara remains holed up in a hotel in Abidjan, protected by U.N. peacekeepers.
Lacine Mara, spokesman for pro-Ouattara forces in the west, said they controlled Duekoue, but a pro-Gbagbo militia operations chief, Yao Yao, told Reuters they had seized only part of it.
Witnesses said combat with guns and heavy weapons continued.
Moise Teki, a doctor in a hospital in Duekoue, said many fighters had come in with bullet wounds.
"The combat ... is very intense," he said by phone. "We don't know who controls the town."
Pro-Ouattara forces have already seized four towns in the west and Gbagbo's forces fear that if they capture enough, they will be able to march south to the port of San Pedro, which ships about half Ivory Coast's cocoa crop.
"The rebels want to take Duekoue and Guiglo so they can easily descend on San Pedro," Yao Yao said. "We won't let them."
The violent stand-off has led to 462 confirmed deaths, according to the United Nations, which is also investigating allegations that 200 African nationals -- from Mali, Burkina Faso, Senegal, Guinea and Togo -- were killed near Guiglo, some 20 miles southwest of Duekoue.
State television has been whipping up resentment by accusing West African foreigners of being behind the rebellion.
Last week, 15,000 pro-Gbagbo youths turned up at army headquarters to enlist, raising fears of all-out war.
Weeks of diplomatic efforts by the African Union (AU) to resolve the crisis have failed, and the AU has simply re-affirmed its position that Ouattara is rightful president.
Ouattara rejected the African Union's nomination of Jose Brito, former foreign minister of Cape Verde, as mediator, arguing that he was too close to Gbagbo.
Brito told Reuters late on Sunday that he had no personal interest in the subject, but as an African he wanted a solution.
The conflict and Western sanctions have sent the economy of what was once the region's economic hub into a tailspin.
Ivory Coast's 80,000 barrel per day SIR refinery said it might be forced to shut from the middle of next month unless it gets fresh supplies of crude oil.
European Union governments said they were discussing toughening their sanctions against Gbagbo.
(Writing by Tim Cocks; editing by David Lewis and Kevin Liffey)