A federal trial over a $100 million investors' lawsuit against Venezuela includes allegations of fraud, hints of an international criminal conspiracy and references to diamonds, junk bonds and a mysterious house fire in Switzerland.

At issue are three-decade old promissory notes issued by a now-defunct government-sponsored Venezuelan bank.

Skye Ventures in Columbus, where the purchase of the notes happened, says Venezuela has confirmed the debts are the government's obligations and must be paid.

Lawyers representing Venezuela say the notes are fakes with forged signatures and were never guaranteed by the government.

A trial expected to last four to six weeks is under way before federal Judge Edmund Sargus after Skye Ventures' 2004 lawsuit survived multiple legal challenges.