The mother of a 15-year-old girl murdered in Fairfax County, Va. says her daughter had become involved with the notorious MS-13 gang, and could not tear away from the group.

Speaking in Spanish, Maria Reyes said her daughter Damaris Reyes Rivas, who was known to friends and family as Alexandra, was a sweet and intelligent girl, but that once involved with MS-13 she began running away from home.

Alexandra made the last break with her family on Dec. 10, after learning her mother was planning to send her to live with family members in Houston to get her away from gang members in the D.C. region.

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Alexandra’s body was found in Fairfax County.

Her mother showed WUSA9 threatening messages relayed to her daughter before her death sent on Facebook Messenger.

Alexandra developed many of her relationships with gang members using social media, her mother said.

The family emigrated from El Salvador, in part, because of violence related to MS-13 in that country.