Buyoya was convicted for "an attack against the head of state" over his role in the killing of the first democratically elected president, Melchior Ndadaye, during a coup d'etat which plunged the country into civil war.
Another three people were sentenced to 20 years in jail for "complicity" in the crimes and a former prime minister Antoine Nduwayo, was acquitted.
Buyoya is currently the African Union's representative in Mali and a respected figure on the continent as well as overseas.
Burundi's ex-president Pierre Buyoya has been sentenced to life in prison in absentia over the assassination of his successor in 1993, according to a court ruling.
Buyoya was on Monday convicted for "an attack against the head of state" over his role in the killing of the first democratically elected president, Melchior Ndadaye, during a coup d'etat which plunged the country into civil war.
Aside from Buyoya, 18 high-ranking military officials and civilians who were close to him received the same sentence.
Another three people were sentenced to 20 years in jail for "complicity" in the crimes and a former prime minister Antoine Nduwayo, was acquitted.
Only five of the accused were present, and the rest were sentenced in absentia. One of the accused said on condition of anonymity that their lawyers had not been informed the ruling was to take place.
Buyoya is currently the African Union's representative in Mali and a respected figure on the continent as well as overseas.
Buyoya, a Tutsi, came to power in 1987 with the help of the army. He stepped down in 1993, when Ndadaye, a Hutu, was elected, but Ndadaye was killed just four months later in an attempted coup by hardline Tutsi soldiers.
The murder led to several years of civil war between the two ethnic groups, in which an estimated 300,000 people died.
Buyoya became president again after a coup d'etat, ruling between 1996 and 2003.
