It appears to be the final showdown for political rivals in Ivory Coast.
Heavy weapons fire has been heard near the presidential palace in Abidjan, where incument leader Laurent Gbagbo is holed up.
It is reported that forces loyal to presidential challenger Alassane Ouattara are attacking the palace, but Gbagbo troops are putting up a fight.
The state tv and radio building has also reportedly been seized by supporters of Ouatarra, who is recognised internationally as the winner of elections last November.
Gbagbo has ignored a fresh opposition deadline to resign.
After taking control of numerous cities across the country, including the capital, Ouattara’s forces swept into Abidjan, the commercial capital.