Dr Michele Ferrari leaves a tribunal in Bologna, Italy in 2004. (Image credit: AFP)

Lance Armstrong's trusted trainer and doctor Michele Ferrari could face criminal charges in addition to his lifetime ban, which was a result of the US Anti-Doping Agency's comprehensive case, in a new investigation by Italian authorities.

The latest investigation, which has been led by Padova prosecutor Benedetto Roberti for the past two years at least, is coming to a close soon, according to the Associated Press. Roberti was reportedly cooperating with a US federal probe run by Jeff Novitzky. That same probe was closed by US Attorney Andre Birotte.

The report states that the investigation is thought to involve some 70 individuals, including 20 athletes in addition to doctors, soigneurs and other staff. Cyclingnews has earlier reported the names of several riders under Roberti's scrutiny, including Giovanni Visconti, Diego Caccia, Moris Possoni and Michele Scarponi, and more recently Leonardo Bertagnolli.

"Armstrong is not under investigation. There are no Americans but there are several foreigners," an AP source stated. "There are no tennis players or athletes from other well-known sports."

Ferrari previously faced criminal charges for sporting fraud based upon the testimony of rider Filippo Simeoni in 2004. Simeoni testified that Ferrari advised him to use EPO and testosterone as part of his training regime, and in 2002 served a short suspension based upon his admissions. His accusation at the time earned him the wrath of Armstrong, who called him a liar in a 2003 interview with Le Monde. Simeoni retaliated by filing a defamation suit, but lost.

Armstrong was forced to distance himself from Ferrari after the verdict, and lashed out at Simeoni during the 2004 Tour de France, chasing him down in a non-threatening breakaway and making a 'zip the lips' gesture.

Although Ferrari won an appeal in 2006 which absolved him of criminal violations, he was still banned for life by the Italian Cycling Federation. Riders who work with him face a sporting ban. Recently Filippo Pozzato was given a three-month ban after admitting to working with Ferrari.

Simeoni's statements have since been corroborated by numerous riders as part of the USADA investigation, including Frankie Andreu, George Hincapie and Christian Vande Velde.

Furthermore, USADA and the Italian investigation uncovered hard evidence that Armstrong was paying Ferrari large sums of money well past 2004 when he claimed to have severed their professional relationship.

Ferrari himself stated that his work with Armstrong and the US Postal team had nothing to do with doping. "I was simply performing functional testing and making training programs," he stated.

"With regards to the alleged testimonies of riders, some were infamous protagonists of unfortunate events and documented lies."