After the killing of a young woman was posted to Facebook, the social media platform said they were investigating the matter. Serena McKay from Sagkeeng First Nation in Canada was allegedly murdered Sunday by two teenage girls after she suffered a brutal beating.

“This was a horrific tragedy, and our hearts go out to the family and friends of Ms. McKay,” a Facebook spokesperson told International Business Times in a statement Thursday. “We have not been able to locate the video on Facebook, and are working with law enforcement as they investigate.”

READ: Facebook Live Death Video, Allegedly Of Serena McKay Murder, Remained Online 

Days after the 19-year-old’s death, it was still unclear if the video remained on the social media platform. “The officers involved in the investigation are in contact with Facebook to ascertain if the video is still there,” Royal Canadian Mounted Police (RCMP) Sgt. Paul Manaigre told IBT in a phone interview Wednesday. “I’ve been personally given links and then it’s dead [when I click on it]. I’m hoping that means it has been removed, but it’s hard to tell.”

McKay’s death was ruled a homicide by police Tuesday. The graphic, stomach-turning video appeared to show two women beating her. They screamed obscenities at McKay as she helplessly said, “I’m so sorry.”  Blood streamed from her nose and she tried to protect her face from her attackers.

The identity of the attackers, ages 16 and 17, cannot be revealed under Canada’s Youth Criminal Justice Act, The Canada Press noted Wednesday. The teenagers were arrested and charged with second-degree murder.

McKay’s community is mourning her tragic death. “Tuesday we had a healing ceremony for our students and staff ... and one of the recurring things that came out was how social media — Facebook, you know — made things even worse by people reposting the video,” Claude Guimond, the principal of her school, told The Canada Press Wednesday.

Police were also worried about the community. “I can't imagine what the family, the community is going through right now. This is a 19-year-old female; this is someone's child, cousin, niece, sister. They're in shock, they're grieving over her loss and they're trying to come to terms with it,” Manaigre told CBC News Tuesday. “The internet, being what it is today, we have to be careful ... what we do. Everything is being put out there. It can be dangerous.”

This is a developing story. Please check back for updates.

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