David McMillan created a flurry of activity online with the Thursday evening tweet in which he also said Prime Minister Stephen Harper "looked like a dumb-ass again."
The reaction was fast and furious, with one post in a tweet alerting American tourists about the Joe Beef restaurant, which "offered a free meal to Al Qaida who killed an American."
McMillan issued an apology Friday, admitting he made a dumb tweet about a subject he did not fully comprehend.
He said it was based on a feeling of empathy.
"It was how I felt at the moment," McMillan tweeted. "I didn't understand the full story. It was a dumb post. Apologies to all offended."
When contacted by The Canadian Press on Friday, McMillan said he had nothing further to say on the matter.
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