TORONTO -- Ontario's troubled air ambulance service has sold two helicopters for US$20 million that will be used to pay down its debt, Ornge said Wednesday.

They're among the 12 helicopters Ornge bought for $144 million from Italian company AgustaWestland -- a deal that's come under intense scrutiny.

The organization, which receives about $150 million a year from the government, is currently under a criminal probe for financial irregularities.

In a statement, CEO and president Dr. Andrew McCallum says Ornge has taken "another important step in addressing legacy issues inherited from previous leadership."

McCallum says the objective has been to recoup as much of the original investment as possible.

Ornge bought 10 AW139 helicopters in 2008 and bought two more for US$11 each, and had been looking for a buyer since the government cleaned house at Ornge and installed new leadership.

"With this sale, we will no longer incur ongoing storage, maintenance and depreciation costs. We are confident that this is a deal which makes sense and minimizes impact on the taxpayer," McCallum said.

The helicopters were sold to Wilmington Trust of Delaware, Ornge said.

A legislative committee has been probing the helicopter deal. It heard that Agusta paid an Ornge spinoff company $6.7 million after it reached a deal on the helicopters, which included the $4.7-million agreement for marketing services.

Both Ontario's auditor general and Ornge's interim CEO said they found no evidence that the work performed reflected the amount of money paid, which has fuelled allegations that it was a kickback. Agusta has denied any wrongdoing.

Former Ornge chairman Rainer Beltzner has testified that even though the board of directors made it clear that they were to approve any major amendments to the deal, they were completely unaware of the $6.7-million payment.

He said he saw documents in January 2012 -- when Ornge's troubles made headlines -- that appeared to show that Ornge was under no obligation to pay for weight upgrades for its new helicopters, but did so anyway.

Ontario's auditor general has criticized the governing Liberals for failing to oversee Ornge, despite giving it $730 million over five years and allowing it to borrow another $300 million.