A photograph was posted to Lt.-Gen. Yvan Blondin's Twitter account Saturday from the funeral of Warrant Officer Patrice Vincent, killed in October by a known jihadist.
Along with the photo, Blondin wrote: "Dear ISIL, thinking of you. Some of my colleagues are in your area. Hopefully, they'll have a chance to drop by."
The tweet was removed on Monday afternoon.
"The comments made by Lt.-Gen. Blondin were inappropriate and have been removed," Johanna Quinney, a spokesman for Defence Minister Rob Nicholson, said in an email.
"Our government remains committed to degrading the ISIL threat to protect Canadians at home, and our interests abroad."
Two days after Vincent was killed, a gunman described by the RCMP as having radical ideology killed a Canadian soldier on honour guard duty at the war memorial and then stormed Parliament Hill, where he died in a gunfight in Centre Block.
Though the prime minister has addressed the attacks both in a televised speech and in Parliament, he has never gone so far as to link them to the combat mission in Iraq.
Jonathan Rose, a political communications expert at Queens University in Kingston, Ont., said it's troubling to see a military commander make the connection.
"It certainly is a marked departure from traditional military communication and is worrisome, because it uses a tasteless image and message to shore up domestic support for a war," Rose said in an email.
"The content trivializes the seriousness of the mission and makes light of casualties."
The communication of the mission's objectives were the subject of intense debate in the weeks before the House of Commons voted on whether to join international air strikes against the al-Qaida splinter group known as the Islamic State of Iraq and the Levant, or ISIL.
Opposition MPs were frustrated in their efforts to learn specific details about the government's pre-combat mission, which involved deploying special forces "advisers" to help Iraqi and Kurdish Peshmerga fighters.
In the end, nearly all of them voted against extending that mission and starting a combat one, in part because the government had so steadfastly refused to disclose details.
Since then, the combat mission has been taking place in almost total secrecy, with the Canadian military denying media access to the air bases where the CF-18s, the refueller and two CP-140 Aurora surveillance planes are located, citing the security concerns of Canada's Kuwaiti hosts.
On Sunday, two CF-18 jet fighters dropped laser-guided bombs in the vicinity of Fallujah, west of Baghdad — the first such Canadian activity in Iraq since the airstrikes were authorized.
But the government has refused to release details of their targets or success, saying it would come at a committee hearing Tuesday, 48 hours after the mission itself.
NDP defence critic Jack Harris said he was waiting for Tuesday's briefing, though he admitted he didn't expect much.
"We'll see how transparent it all is tomorrow," Harris said.
— With files from Murray Brewster in Kuwait
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