Disgraced former US lobbyist Jack Abramoff has been jailed for nearly six years for conspiracy and fraud.
Abramoff has been co-operating in a wider inquiry
Abramoff - who had close links to top Republicans - had pleaded guilty to the charges, which relate to the purchase of a fleet of casino boats in 2000.
In a separate case, he has admitted to tax evasion, defrauding his clients and conspiring to bribe public officials.
An ongoing federal inquiry is said to be focusing on his dealings with up to 20 politicians in Congress.
The case has sent shockwaves through Washington's political establishment, the BBC's Jonathan Beale in Miami says.
The federal judge in Miami gave Abramoff a total of 70 months - five years and 10 months - in jail on Wednesday.
The case related to the purchase of the SunCruz Casinos gambling fleet.
Abramoff and his former business partner - Adam Kidan - were accused of faking a wire transfer of $23m (£13m) to obtain loans for the purchase of SunCruz.
The sentence was the minimum under his plea agreement in the case.
Kidan was also sentenced to 70 months in jail. Both were also ordered to pay $21.7m (£12.5) in restitution.
Abramoff said in court that the case was "incredibly painful" for him personally, but also for his family and his friends.
"In the past few years I have begun the process of becoming a new man," he said.
Abramoff - along with Kidan - does not have to begin serving his sentences for another 90 days in order to be able to continue co-operating in the separate Washington case.
ABRAMOFF SCANDAL TIMELINE
1995: Abramoff signs up his first casino-rich tribe as clients
1997: Arranges for lawmakers to visit the Marianas - more trips will follow
2000: Buys SunCruz Casinos
2001: Forms partnership with Michael Scanlon
2004: Reports emerge that they have received $45m from tribes - Senator McCain launches inquiry
2005: Abramoff and Adam Kidan indicted over SunCruz purchase
Jan 2006: Abramoff admits to fraud, tax evasion and conspiracy to bribe. A day later he pleads guilty to wire fraud and conspiracy in SunCruz case
Mar 2006: Abramoff sentenced to 70 months in jail
In January, Abramoff also pleaded guilty to defrauding the Native American tribes that were his clients, to tax evasion and to conspiring to bribe public officials.
The wide-ranging federal inquiry began in 2004 after reports that he and business partner Michael Scanlon had received some $45m (£26m) from Native American tribes with casinos.
Abramoff was accused of exploiting the tribes to enrich himself and his friends, and offering politicians in both houses of Congress lavish meals, tickets to major sporting events and trips.
He was a major fundraiser for Republican politicians, including the former house republican leader Tom Delay.
Most have now deserted him and denied any wrongdoing, says our correspondent.
No date has been set for sentencing in the second case, but his co-operation with investigators is likely to lead to a reduced jail term.