The girl went unconscious at an apartment on the 2900 block of John Marshall Drive in Seven Corners around 6 p.m. on Monday, Dec. 5, Fairfax County police said.
The friend on the other line alerted a family member, who found the girl unresponsive and called 9-1-1, police said.
The teen was rushed to a local hospital, where she was pronounced dead.
Fentanyl is a synthetic opioid that is approximately 100 times more potent than morphine. As little as 2mg is enough to amount to a deadly dose.
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