Forces backing Ivory Coast's internationally-recognized president, Alassane Ouattara, have stormed the home of incumbent leader Laurent Gbagbo in a bid to force him to surrender.
Witnesses report hearing heavy gunfire around the residence in Abidjan, where Gbagbo is holed up in an underground bunker with his family.
On Tuesday, Gbagbo appeared ready to surrender, but later gave phone interviews insisting that he won last year's presidential election and indicating that he would not give up power.
Aides to Ouattara say the forces attacking Gbagbo's residence have been told to capture him alive.
A Gbagbo spokesman says French forces are involved in the assault, an allegation French officials have denied.
Ivory Coast has been mired in political crisis since December, when Mr. Gbagbo rejected election results showing that Ivorians had chosen Ouattara as president.
Months of international mediation efforts failed to convince Gbagbo to leave power peacefully. Pro-Ouattara fighters launched a nationwide offensive last week, seizing towns and cities across Ivory Coast, and driving pro-Gbagbo forces back to Abidjan.
Fighting in Abidjan eased on Tuesday. The U.N. mission in Ivory Coast said three Gbagbo generals called to say they were ordering troops to lay down their weapons and turn them over to the U.N. One of the three is Mr. Gbagbo's army chief of staff, Philippe Mangou, who earlier had called for a cease-fire.
France's foreign minister, Alain Juppe, said France and the United Nations want Mr. Gbagbo to sign a document in which he agrees to renounce power and accept Mr. Ouattara as president. The spokesman for the U.N. mission in Ivory Coast, Hamadoun Toure, said that if Gbagbo wants to surrender, the United Nations would help protect him.
Hundreds of people have died since the post-election fighting began in December, including many civilians. The U.N. has begun investigating reported mass killings in the western town of Duekoue last week.
The U.N. says up to 1 million people have fled their homes since violence began in December. More than 100,000 have fled to neighboring Liberia, with smaller numbers going to Ghana.
Some information for this report was provided by AP, AFP and Reuters.