"This is an extremely unfortunate example of an advertiser scraping an image from the Internet and using it in their ad campaign," Facebook said in a statement sent to the Toronto Star. "We apologize for any harm this has caused."
Facebook said it removed the ad and permanently deleted the account of Ionechat.com, the dating site that used the photo of the deceased 17-year-old.
The advertisement featured a photo of the teen and the caption: "Find Love in Canada! Meet Canadian girls and women for friendship, dating or relationships."
Lonechat.com could not be reached for comment, the Star said.
Parsons died in April when she was taken off life support following a suicide attempt.
Her parents said Parsons acted in desperation after she was sexually assaulted and then bullied.
"I am completely bewildered and disgusted by this," the girl's father, Glen Canning, said. "This is my daughter, Rehtaeh. They have her in an ad for meeting singles. I don't even know what to say."
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