Former Indian railways minister Laloo Prasad Yadav has been sentenced to five years in prison in a notorious case known as the “fodder scam”.
He was jailed on Monday after being found guilty of embezzling state funds intended to buy food for cattle while he was Bihar state chief minister.
He has always denied the allegations. His family has said he will appeal.
The sentencing is seen as a landmark step in tackling corruption in India where it is a major national issue.
Yadav now becomes one of the first politicians to lose his parliamentary seat after a recent Supreme Court ruling which bans convicted legislators from holding office.
On Wednesday, the government withdrew a controversial order which would have overturned the Supreme Court ruling and allowed convicted MPs to run for elections while appeals were pending.
Delivering its judgement on Thursday, the special court in Ranchi in the eastern state of Jharkhand also ordered Yadav to pay a fine of 2.5m rupees ($40,481; £24,938).
Arvind Singh, joint secretary of the bar association in Ranchi, said Yadav would serve five years of “rigorous imprisonment”.
He is among 45 people, including senior bureaucrats and politicians, who have been convicted by the court.
The scandal involved embezzlement of 9.5bn rupees ($151m; £94m) meant for buying cattle fodder.
The case first came to light in 1996, a measure of how long it can take for justice to be delivered in India.
Another former Bihar chief minister, Jagannath Mishra, was also convicted on Monday and has been sentenced to four years in jail.
There were a total of 56 defendants in the case. During the trial, seven of them died, two decided to give evidence for the prosecution, one admitted to the crime and one was discharged.
Laloo Yadav is one of India’s most colourful politicians. He leads the Rashtriya Janata Dal party in Bihar and has long been an ally of India’s Congress party-led coalition government in Delhi.
He resigned as chief minister of Bihar after the allegations of corruption arose. His wife Rabri Devi was installed in his place.
Yadav’s Rashtriya Janata Dal party lost power in state elections in 2005.
Correspondents say the government has been beset by several high-profile corruption cases in recent years and public anger against politicians and officials seen as corrupt is at unprecedented levels.
The Delhi-based election watchdog, the Association for Democratic Reforms, says that there are 1,460 serving lawmakers facing criminal charges.
In the 543-seat lower house of parliament alone, more than 150 MPs are said to be facing criminal charges.
The Supreme Court has recently been trying weigh in on the issue. Last week, the court gave voters the right to reject all candidates in elections – the judges said that such a move would help cleanse the political system in the country.