By Christian Akorlie
ACCRA (Reuters) - A sea of Ghanaians clad in traditional red-and-black mourning cloth paid last respects on Friday to Ghana's late President John Atta Mills, who died suddenly after helping transform his nation into one of Africa's fastest growing economies.
More than a dozen heads of state, mainly from West Africa, and U.S. Secretary of State Hillary Clinton joined thousands of Mills's mourning countrymen in the seaside capital as his coffin was carried on a gun carriage followed by wreath bearers.
Some mourners, many of them weeping and holding pictures of the late president, had gathered before dawn in Accra's Independence Square to secure a spot for the funeral.
"I saw him some few times during his visits to our region. I heard him preach peace all the time in his speech. So I wanted very much to be here to bid him farewell," said 65-year-old Lawson Nartey, who was dressed in black with a red ribbon around his neck.
Mills, who had been due to stand for re-election in December, died suddenly on July 24. The cause of his death has not yet been disclosed.
Within hours, John Dramani Mahama, Mills's deputy, had been sworn-in by parliament as his replacement, removing concerns cover political instability seen elsewhere in Africa following the death in office of a sitting president.
"This is history, the first time we've lost a president in office, and I very much wanted to be part of it," said Robert Ananga, 40, who traveled from the northern city of Bolgatanga, some 850 km (510 miles) from Accra.
President Mahama, who spoke during the two-hour burial ceremony marked by Bible readings, prayers and singing, described Mills as a man who cemented stability in Ghana.
"I am in no doubt that the unifier and the man of peace that our late president was, in passing on to glory, will be a catalyst for our country to consolidate the peace and forge ahead in unity," Mahama said.
During his term, Mills was credited with guiding Ghana's transformation into the Gulf of Guinea's newest oil exporter, and overseeing one of Africa's fastest growing economies, which is already a major cocoa and gold producer.
The ruling National Democratic Congress (NDC) party has said?Mahama will be their candidate in elections still planned for December, with former Central Bank Governor Kwesi Amissah-Arthur set to be his running mate.
While West Africa has seen a number of coups and contested votes in recent years, the smooth transition after Mills's death comes after Ghana was also widely praised for the handling of the tight election in 2008 that brought Mills to power.
Nana Akufo-Addo, who Mills defeated in the 2008 vote, will take on Mahama in what is expected to be a close contest.
The swift nomination of Mahama appears to ease some concerns over a bitter contest within the NDC but analysts have flagged potential strains on Ghana's economy and the cedi currency of a year of election-related spending.
(Writing by David Lewis; Editing by Richard Valdmanis and Michael Roddy)