Jailer E K D Duminda, who used to escort Fonseka to the High Court to attend proceedings of a case against the former military commander, has been interdicted and asked to explain why the prisoner in his custody was allowed to speak to reporters, according to local media.
Apart from the jailer, a driver of the prison has been suspended.
Fonseka was jailed for 30 months after he was convicted by a court martial of violating military procurement procedures.He also faces several other criminal charges before civilian courts and is regularly brought out of the high- security Welikada prison for hearings.
During such visits, Fonseka has been freely talking to reporters.
Fonseka's Democratic National Alliance (DNA) is challenging his incarceration and has accused the government of leading a political vendetta against a man who challenged President Mahinda Rajapaksa in the January presidential polls.
A military court also stripped Fonseka of his rank and pension and withdrew medals he earned during his 40-year military career after he was convicted of another charge of dabbling in politics while in uniform.
Fonseka had led the military in successfully crushing the Tamil Tigers and ending decades of ethnic war in May last year.However, he fell out with Rajapaksa over who should take credit for the spectacular military success.
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