TORONTO -- Former Ornge CEO Chris Mazza is being asked to face more questioning next week by members of a legislative committee looking into Ontario's troubled air ambulance service.

An emotional Mazza faced a day-long grilling by the committee last week, and said he didn't know what went wrong at Ornge, but that the Liberal government never told him he was veering off course.

The Progressive Conservatives confirmed Wednesday that the committee has more questions for Mazza, so he is being recalled to testify again, but the date still has to be worked out with his lawyer.

The committee meets again on July 31, Aug. 1 and 2.

"Unfortunately, Mr. Mazza's testimony last week raised more questions than it answered, not the least of which is where did much of this money go," said Conservative MPP Frank Klees, who sparred frequently with Mazza at the committee.

"As the CEO surely he must know where the funds from the marketing agreement went, so it's questions like that that we intend to pursue."

Provincial police are conducting a criminal investigation into financial irregularities at Ornge, including a $6.7-million marketing services agreement that Italian helicopter manufacturer AgustaWestland paid to a for-profit Ornge spinoff firm shortly after Ornge purchased 12 helicopters for $144 million.

Mazza had set up a complex web of Ornge spinoff companies that the government has since shut down. It also fired Mazza and is now looking for a new CEO for the taxpayer-funded air ambulance service, which has been mired in controversy amid allegations that public money was used for personal gain.

It took two Speaker's warrants to get Mazza to finally appear at the committee last week. His doctors said he had been suffering emotional problems and was unable to testify previously.

A drained-looking Mazza left the committee saying he was "exhausted" after his testimony, but Klees said he expects the former Ornge CEO will appear again next week.

"One of the things he certainly demonstrated to the committee last week when he did testify is that he's very capable of testifying," said Klees.

"He may not remember a lot of things -- and I think personally that's selectively -- but he's certainly very capable."

Blaming frequent memory lapses before the committee on his emotional problems, Mazza denied that he masterminded an alleged kickback scheme with AgustaWestland after it sold Ornge a fleet of helicopters.

Mazza said he regretted that his $1.4-million salary, which was hidden from taxpayers, had become a lighting rod for public anger.

Health Minister Deb Matthews is also being recalled to face more questions, and is expected to appear Tuesday, before Mazza makes his second appearance.