By Stephanie Busari, CNN

(CNN) -- Kofi Annan, the former UN secretary-general and Nobel Peace Prize winner, has been laid to rest Thursday in his home country of Ghana.

Thousands of mourners gathered in the Accra International Conference Center to pay their last respects during an emotional funeral service on Thursday.

Annan's widow, Nane Maria Annan was visibly moved as solo singer Alice Twum gave a rendition of the hymn "It Is Well."

During her eulogy, the widow told the congregation: "Kofi always believed that his inner strength and sense of hope came from his deep roots here and I want to thank Ghana for giving me such an extraordinary human being.

"My love, you are now back home where you started your long journey. But may your wisdom and compassion continue to guide us, wherever we are," she added.

Annan's son Kojo and daughter Ama also paid tribute to their father during the three-hour ceremony.

Kojo, 45, said: "To the rest of the world, he was a global statesman par excellence. To me he was just Daddy. His singular gift is that he believed in humanity's potential. He believed in everyone's ability to achieve extraordinary things if given an opportunity."

Annan, the first black man to lead the United Nations, died in August at 80 after a brief illness.

His body was flown back to Ghana from Switzerland on Monday ahead of the funeral.

The Ghanaian diplomat was the seventh UN secretary-general, serving from 1997 to 2006, and was the first to rise from within the ranks of the UN staff.

Annan, described by former Nigerian Finance Minister Ngozi Okonjo-Iweala as "Africa's foremost son," led the United Nations at a time of raging global terrorism; his efforts at combating conflicts in Africa, Asia and the Middle East won him a Nobel Peace Prize in 2001.

Current UN Secretary General António Guterres praised his close friend as an "exceptional global leader."

"He had a gentle voice that made people smile and think of music but his words were also tough and wise. Kofi Annan was courageous speaking truth to power while subjecting himself to intense scrutiny," Guterres said.

"Kofi Annan was the United Nations and the United Nations was him," Guterres added.

World leaders who attended the funeral include six African presidents: Nana Akufo-Addo of Ghana, Emmerson Mnangagwa of Zimbabwe, George Weah of Liberia, Alassane Ouattara of Cote d'Ivoire, Hage Geingob of Namibia and Mahamadou Issoufou of Niger.

Many of Ghana's traditional rulers, clad in their customary black and red flowing robes, were also present during the service.

Funeral rites are deemed very important in Ghana, and one of the traditional rulers told CNN that Annan should have been laid to rest in his ancestral home in the east of the country, with other royal family members.

Nana Annom III told CNN: "Kofi Annan is a royal so he should have been buried with the others where he was born. He is an international figure so it was permitted for him to be buried in Accra," he said.

Annan's cortege was taken a few meters away from the conference center to the military cemetery, where he was given full military honors, including a 17-gun salute.

The UN will hold two other ceremonies in Annan's honor later this month in Geneva, Switzerland, and in New York.