A pastor of a megachurch in Houston, Texas is facing 20 years in prison after he was indicted on charges of defrauding investors by allegedly selling them worthless Chinese bonds.

Pastor Kirbyjon Caldwell and his business partner Gregory Smith were indicted with multiple charges on Thursday after allegedly selling the bonds to nearly 30 "vulnerable and elderly" investors.

According to court documents, Caldwell and Smith amassed at least $3.48 million in the sales from April 2013 to August 2014.

The bonds, which were issued after World War II, had reportedly lost their value after the Chinese government that issued them was overthrown by the Communists in 1949.

Smith, 64, and Caldwell, 55 have been charged with six counts of wire fraud and one count each for conspiracy to commit wire fraud.

The two men are both facing 20 years in prison and could be forced to forfeit their assets if convicted. They could also both face an additional 10 years if found guilty of four counts of money laundering and conspiracy to commit money laundering.

Caldwell, who serves as the senior pastor at Windsor Village United Methodist Church, is already planning to turn himself into the authorities, according to his lawyer Dan Cogdell.

The lawyer denied claims his client knew the bonds had no value at the time they were sold.

"I know Kirbyjon, the community knows him well. ... He's an icon in the Houston area and he's 100 percent, absolutely innocent of these charges," Cogdell told KTRK on Friday.

"He absolutely believed these bonds were worth -- in fact, he believed these bonds were worth more than he sold them for. He was the biggest investor in these bonds," the lawyer added.

Smith, a financial planner from Louisiana, reportedly told investors that purchasing the bonds was "risk free" and that he had invested $250,000 of his own money.

Prosecutors have charged that Smith and Caldwell had used the investors' money to buy vehicles and pay for personal expenses, such as credit card debt and mortgages.

Cogdell said that the pair had already refunded almost $1 million to investors who had demanded their money back.

The Daily Mail reported that Caldwell served as spiritual adviser to Presidents George W. Bush and Barack Obama, and delivered the benediction at both of Bush's inaugurations.  He also reportedly officiated the wedding of Bush's daughter, Jenna, in 2008 at the family's ranch in Texas.