Heavy gunfire was heard Wednesday outside Guinea-Bissau's presidential palace just three days after the country's presidential and legislative elections, with both major candidates having claimed victory, an AFP journalist on the scene witnessed.As shots rang out, people and vehicles fled from the area, the AFP journalist observed.Official provisional vote results are expected Thursday in the tumultuous west African country, which has experienced four coups since independence, as well as multiple attempted coups.Both the current president, Umaro Sissoco Embalo, and opposition candidate Fernando Dias have declared victory.A passerby fleeing from the chaotic scene told AFP that