Mr Bongo was ousted in a military coup in August last year
Gabon's deposed President Ali Bongo and two of his sons have gone on hunger strike to protest against their alleged subjection to "acts of torture and barbarity", the family's lawyers say.
Mr Bongo was ousted in a military coup in August last year, shortly after he won a disputed presidential poll.
He was then confined to his house in the capital, Libreville, along with two of his sons, Jalil and Bilal.
The ruling junta also placed his wife Sylvia Bongo and eldest son Noureddin in prison, awaiting trial on corruption allegations.
In a statement, their lawyers alleged that Noureddin and Sylvia were beaten and strangled while in detention.
They also allege that Noureddin was tortured, whipped and "even electrocuted with a taser".
Gabonese authorities are yet to comment on the allegations.
The ousted president, aged 64, had led the oil-rich country since 2009 when he succeeded his father who had been in power for more than 40 years.
The family' lawyers say they have also filed a complaint with the Paris judicial court, a week before Gabon's junta leader Gen Brice Oligui Nguema is due to visit France.
