Canada's first air strikes in Iraq blew up a construction site operated by Islamic State militants, destroying bulldozers and a dump truck used by the extremists to build obstructions and defensive positions.

This was the intended target Sunday near Fallujah, when CF-18 warplanes dropped their first bombs in Canada's combat mission in Iraq, sources say.

News of damage from the first Canadian bombs comes as Stephen Harper says it will be up to Iraqis and soldiers from other countries in the region to ultimately defeat the Islamic State.

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It's not yet known whether Sunday's strikes killed militants or civilians but the Department of National Defence is holding a media briefing Tuesday to review the strike on heavy equipment.

"They were using this stuff to build infrastructure to continue their fight and that's why it was a target," a source familiar with the air strikes said of Islamic State fighters.

Canada's stated goal in dropping bombs on the jihadi forces in Iraq is to help beat back the destructive movement that has wreaked havoc across parts of Iraq and Syria.

The commander of the Royal Canadian Air Force made it personal on Twitter, though, suggesting the air strikes were payback for an attack on a Canadian soldier last month in Quebec. Warrant Officer Patrice Vincent was slain in an attack by a man apparently inspired by the Islamic State, also known as Islamic State of Iraq and the Levant (ISIL).

On Saturday, Lieutenant-General Yvan Blondin tweeted a photo from Warrant Officer Vincent's funeral with this message: "Dear ISIL, thinking of you. Some of my colleagues are in your area. Hopefully, they'll have a chance to drop by."

He was publicly reprimanded Monday by Defence Minister Rob Nicholson's office and the tweet deleted.

"The comments made by Lt.-Gen Blondin were inappropriate and have been removed. Our government remains committed to degrading the ISIL threat to protect Canadians at home, and our interests abroad," said Johanna Quinney, press secretary to Mr. Nicholson.

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Another source familiar with Sunday's bombing mission said the construction site hit by Canadian bombs was near a dam. They did not elaborate but Islamic State forces seized control of the Fallujah Dam on the Euphrates river earlier this year and used the water to flood and destroy sites. Militants also used the dam to cut off water to some districts.

Mr. Harper, meanwhile, said aerial bombardment of the Islamic State forces is not enough to defeat the group.

Asked if it was inevitable that Western countries deploy ground forces to Iraq, the Prime Minister said it's up to Iraqis themselves to solve the conflict.

He said a ground war will be up to Arab countries and that Baghdad will have to work to win over parts of Iraq now controlled by Islamic State rebels.

"We all recognize that it has to ultimately be pushed back on the ground. Part of that is a military effort on the part of those in the region, part of it is also a political settlement in Baghdad that allows those parts of the country that are presently occupied by ISIL to see themselves as part of the governance and part of the national life of the country," Mr. Harper said.

"To really be effective, it has to be the Iraqis themselves who take that responsibility."

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U.S. warplanes have pounded Islamic State forces for months. Targets have included training camps, machine-gun firing positions, bunkers, ammunition caches, armoured vehicles and tanks.

With a report from The Canadian Press