Paris  - Omar Bongo, the autocratic president of the West African nation of Gabon, died Sunday at the age of 73, the online edition of French weekly Le Point reported, quoting a French government source.

Africa's longest-serving head of state suspended his powers on May 6, ostensibly to mourn the death of his second wife Edith Lucie, who passed away in Rabat, Morocco, on March 14 after a long ailment.

He then checked into a private clinic in Barcelona, Spain, suffering from a tumour, which ultimately claimed his life.

Bongo was president of Gabon, a former French colony, for 41 years.

His death came as French authorities probed whether he had used hundreds of millions of dollars of Gabonese public funds to buy lavish properties in France. Bongo's family apparently owns 39 luxury properties in France.

The president was often accused of diverting oil money for his own personal use. Elf Aquitaine, the former French oil group, allegedly gave Bongo tens of millions of euros annually to allow it extract Gabon's oil.

Bongo was viewed as one of the ultimate political survivors, who used corruption and cronyism as a tool to keep himself at the top for more than 40 years. The president ruled virtually unchallenged during his reign, no mean feat in a part of the world where coups have long been commonplace.

Bongo took up the mantle as the world's longest-serving leader when Cuban President Fidel Castro stepped down in 2008. (dpa)