The death of a 16-year-old McLean girl in August has been ruled an accident caused by the adverse effects of heroin and an over-the-counter antihistamine, according to the state medical examiner’s office.

Fairfax County police found the body of Emylee Lonczak on Aug. 23 in the Vienna area, police said. The McLean High School student left home on Aug. 21 with two adult males and then traveled out of the state to purchase drugs from another man, according to a search warrant.

Members of the group then used the drug, before returning to Fairfax County in the early hours of Aug. 22 after realizing that Lonczak needed medical attention, according to the search warrant. None was sought.

Investigators determined Lonczak died later that morning, and her body was concealed in the 8200 block of Madrillon Estates Drive, police said.

Police filed several search warrants to gain access to the Facebook accounts of Lonczak and her associates in September. At the time, investigators said they were exploring filing charges of contributing to the delinquency of a minor in the case.

A police spokesman reached Wednesday evening said they had not yet received word of the medical examiner’s ruling, and he was unsure whether any charges had been filed in the case.