Lance Armstrong sued by US government

The US government will join the burgeoning case against disgraced cyclist Lance Armstrong, who's been accused of defrauding the US Postal Service by accepting millions in sponsorship funds from the government while continuing to illegally dope, flouting the rules of the sport. 

The Justice Department filed court documents describing the case against Armstrong (as well as team manager Johan Bruyneel and Tailwind Sports LLC late on Tuesday, wrote Reuters, and will add its formal complaint to the 2010 whistle-blower lawsuit placed by fellow cyclist Floyd Landis.

Read more from GlobalPost: Lance Armstrong under "active criminal investigation"

"Defendants were unjustly enriched to the extent of the payments and other benefits they received from the USPS, either directly or indirectly," said the complaint of Armstrong, according to CNN.

It's a complaint that could lead to a massive payout for the US government, which seeks to collect triple the amount of the $40 million it spent on the US Postal Service cycling team from 1998 to 2005 under the False Claims Act.

Meanwhile, Armstrong's attorney, Elliot Peters, defended his client against the government allegations to the BBC. "The US Postal Service benefited tremendously from its sponsorship of the cycling team," said Peters. "Its own studies repeatedly and conclusively prove this. The USPS was never the victim of fraud."

"Lance Armstrong rode his heart out for the USPS team, and gave the brand tremendous exposure during the sponsorship years," he added.