Guinea-Bissau's President Umaro Sissoco Embaló has been arrested by armed men, government sources told the BBC after gunfire was heard near the presidential palace.

Witnesses in the capital, Bissau, heard gunshots at around 13:00 GMT but it was not immediately clear who was involved in the shooting.

The reports come three days after a presidential election in which the main opposition candidate was disqualified.

The poll's results were expected on Thursday - both Embaló and his closest rival Fernando Dias have claimed victory.