Article published on the 2009-06-09 Latest update 2009-06-09 13:19 TU
In a televised address on Monday night, defence minister Ali Ben Bongo renewed public appeals. "I am calling for calm and serenity of heart and reverance to preserve the unity and peace so dear to our late father," he said after his ministry announced the closure of air, land and sea borders.
On Monday, police and troops were posted at key points across the capital, Libreville, while residents complained that Internet access to international news was cut.
As Gabon entered a 30-day official mouring period, tributes for the president, whose death was confirmed on Monday, continued. African Union peace and security commissioner Ramtane Lamamra told French news agency AFP that "a very important son of Africa" had gone.
Chadian president Idriss Deby expressed profound shock at the death of his friend and announced a 3-day mourning period.
Tributes also came in from the Central African Republic, Congo-Brazzaville, Ivory Coast, Morocco's King Mohammed VI and Senegal. Elsewhere, US president Barak Obama praised Omar Bongo's peacemaking efforts and commitment to environmental protection.
United Nations chief Ban Ki-moon paid tribute to the president's key role in the search for peace across the African continent.
But in Paris, former French judge, Eva Joly, who is in charge of investigating corruption into the French state-owned oil company Elf Gabon says it is time for a change.
"He (late president Omar Bongo) is the symbol of what is known as 'France-Afrique', this France Africa network. Through him a lot of money left Gabon to finance French politicians. Today there might be hope for the Gabonese to have a new regime."
Bongo was Africa's longest serving ruler. He came to power in 1967 with French support and ruled over a state that became rich on abudant oil resources.
His death has raised fears of a power vacuum. Under the constitution, the leader of the Senate, Rose Francine Rogombe, should take over and organise elections within 45 days.
Opposition leaders are already claiming that Ali-Ben Bongo has been lined up to succeed his father.
Alioune Tine, head of RADDHO, a Senegalese human rights association, believes the country is facing an uncertain future.
"There are several problems. First is the fight to become president between Ali Bongo and his sister, Pascaline. The family will find it difficult to stay in power so they may decide to do it by force, There is also the threat which comes from Gabon's borders with other countries such as Equatorial Guinea and Congo Brazzaville."