OTTAWA -- The military says Canadian CF-18 fighter jets conducted a single attack in Iraq last week, leading a coalition strike that destroyed a factory making improvised explosive devices.

Navy Capt. Paul Forget says the attack last week was a success.

He says coalition air attacks and Iraqi ground efforts continue to degrade the operational ability of the group known as the Islamic State of Iraq and the Levant.

Since the Canadian mission began last fall, CF-18s have flown 328 missions.

A Canadian Polaris tanker aircraft has flown 82 sorties and delivered more than two million kilograms of fuel to coalition aircraft.

Forget says another 91 missions flown by Canadian Aurora reconnaissance planes bring the total number of Canadian sorties to 501.

The update came on the same day that the government fufilled a promise to release more information on the cost of the war against ISIL.

National Defence, through the latest round of supplementary spending estimates, asked for a budget top-up to the end of the fiscal year of $139 million, of which $122 million was for the combat mission in Iraq.

An additional $17 million is being sought for expenses related to Canadian involvement in the NATO mission to eastern Europe, which took place in the aftermath of Russia's annexation of Crimea.

Until Defence Minister Jason Kenney finally broke the government's silence this week, the Conservatives had been under fire for refusing to disclose the cost of deploying CF-18s and special forces advisers in the war-ravaged nation.

The additional budget request released Thursday shows that the bombing campaign itself accounts for $73 million of the Iraq war costs.

Canada has also deployed up 69 special forces advisers in northern Iraq, who took along vehicles and other specialized equipment.

Kenney warned earlier this week that the costs would increase if the government chooses to extend the mission -- something that by all indications appears to be a likely possibility.