Now an opposition lawmaker, Fonseka, who led Sri Lankan Army's spectacular victory over the LTTE last year, was found guilty of corruption in defence deals at a hearing held today, sources said.
The second court martial has recommended to the President a three-year jail term for Fonseka, they said.
The recommendations will be sent to the President, who has to approve them as the Commander-in-Chief of the Armed Forces.
The punishment will be officially declared only after the President signs the order, the sources said.
Fonseka had been charged with favouring an arms firm headed by his son-in-law in defence deals during his time as Army chief.
President Mahinda Rajapaksa is currently travelling to the US, and is scheduled to return next week.
The 59-year-old former Army Chief, who is now a parliamentarian, was convicted by a court martial last month for dabbling into politics while in active service.
The court had ordered that Fonseka be stripped of his rank, pension and medals -- a decision that was ratified by Rajapaksa. The ex-general termed his dishonourable discharge as a "joke".
Fonseka is in custody since his arrest in January after his loss to Rajapaksa in the presidential election.
Fonseka, who was once close to the President, fell out with him in the last days of the war, and later challenged him in the presidential election.
The opposition has called the targeting of Fonseka by the Rajapaksa government as political witch-hunting.
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