A 15-year-old Florida boy identified as a “person of interest” in his grandmother’s killing has been detained in upstate New York while allegedly attempting to cross the border into Canada, PEOPLE confirms.
On Nov. 22, Kristina French, 53, and her grandson were reported missing by the teen’s father, who returned from vacation to find the victim’s Neptune, Florida, residence ransacked, according to a statement from the Jacksonville Sheriff’s Office.
The gun safe was also empty, the statement says.
According to the statement, the ninth grader was allegedly driving French’s 2015 Dodge Dart at the time he was detained by U.S. Customs and Border Protection agents on Nov. 24. PEOPLE is not identifying the teen, who has been charged with grand theft auto.
Before the teen was detained on Nov. 24, French’s body was found in a shallow grave behind her home.
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The statement does not provide a cause of death in this case, and a police spokeswoman tells PEOPLE no additional information will be released on the investigation, which is ongoing.
Police are also not commenting on a possible motive.
PEOPLE was unable to reach the boy’s parents for comments Monday.
The teen was last seen in school on Nov. 17.
Before being apprehended in New York, security cameras recorded footage of the teen in Pennsylvania, according to the statement.
The teen’s mother has issued statements to local media, asking the public to refrain from jumping to conclusions.
She also told a reporter for the local CBS affiliate she is not letting law enforcement interview her son.