Natural Resources Minister Gary Lunn said Sunday he had no way of anticipating the Chalk River reactor crisis, despite an auditor general report sent to him in the fall that warned of lingering safety issues at the site.

The report was issued in September and Lunn told CTV's Question Period that he was briefed on the audit during the first week of October, about two months before the reactor was shut down.

"It was a great report but it said absolutely nothing about the situation," said Lunn. "It never once raised licensing issues."

The report warned of highlighted "three strategic challenges" Atomic Energy of Canada Ltd. faced, including "the replacement of aging facilities at Chalk River Laboratories (CRL)."

Lunn said the auditor general's concerns were focused on MAPLE reactors at Chalk River that had yet to come online.

"There's absolutely nothing, nothing in this auditor general's report that would have allowed me to foresee that we were going to have this problem that we did in early December. It's simply not in the report."

Lunn also said that AECL, a Crown corporation, never alerted him to the fact the Chalk River reactor was operating without a back-up pump in violation of its licence.

"I was never told by the Canadian Safety Commission or AECL that AECL was under a potential licence violation," he said. "It was not something I would have been briefed on immediately. So, again, I would not have known this."

Lunn has placed blamed the head of Canada's nuclear watchdog for the reactor crisis, which shut down production of much-needed medical isotopes for cancer patients.

Earlier this month he fired Linda Keen as president of the Canadian Nuclear Safety Commission late Tuesday. She had been named the head of the independent agency by the previous Liberal government.

On Sunday, Lunn said she was fired because she was willing to put lives at risk by extending the closure.

"There has to be accountability. This was a very serious crisis. We believe the former president and CEO of the Canadian Nuclear Safety Commission was prepared to put people's lives at risk," Lunn said. "We cannot allow ourselves to be put in this situation again."

Keen's removal followed suggestions from Prime Minister Stephen Harper that her decision to block the reactor from restarting was politically motivated.

The head of the Public Service Alliance of Canada described that accusation as "alarming."

Union president John Gordon said Harper could seriously undermine the way the nation is run by accusing bureaucrats who were hired by the previous Liberal government of partisanship.

"Governments come and governments go. The public service has to be still run," Gordon told Question Period. "It's run by bureaucrats who understand the public service and understand the needs. No government should be making statements like that."

Chalk River closure

Parliament's natural resources committee is probing the circumstances surrounding the Chalk River closure, which led to a worldwide medical isotope shortage.

In December, the CNSC tried to keep the reactor offline until safety upgrades were finished. But the House of Commons unanimously voted to reopen the reactor and resume isotope production.

Gordon, meanwhile, said the government had a history of sidestepping responsibility by pointing the blame at established bureaucrats.

"Anything that comes up that they feel they want to not take any heat for, they blame the government before them," he said.

"Their government should be a responsible government, and they should be carrying out the task of governing the country, and not just blaming somebody else."

The reactor, operated by AECL, stopped production for scheduled repairs on Nov. 18 and was expected to restart within five days.

But the CNSC -- responsible for setting licensing, health and safety rules for the country's nuclear facilities -- refused to allow the reactor to restart after finding it had been operating for 17 months without a backup emergency power system for its cooling pumps.

In December, emergency legislation passed by Parliament side-stepped the CNSC's objections and allowed AECL to restart the reactor for 120 days in order to alleviate the isotope shortage.

Gordon said the decision to reopen the plant was hastily done by leaders who "fast tracked" the decision through the House of Commons without meeting with Keen to discuss the closure.