A 16-year-old McLean girl who was found dead last month was part of a group that used illegal narcotics in the hours before her death, according to search warrants filed in Fairfax County court.

Emylee Lonczak, who attended McLean High School, left home on Aug. 21 with two adult males and then traveled out of the state to purchase an unspecified drug from a third adult male, according to a search warrant. Members of the group then used the drug.

In the early morning hours of Aug. 22, the group returned to Fairfax County after realizing that Lonczak needed medical attention, according to a search warrant. However, none was sought.

Investigators determined that Lonczak died later that morning and that her body was concealed in the Vienna area.

Police filed several search warrants in Fairfax County Circuit Court to gain access to the Facebook accounts of Lonczak and the men she was with that night. Police are exploring filing charges of contributing to the delinquency of a minor in the case, according to the search warrant.

Because they have not been charged with crimes, The Washington Post is not naming the men.

Investigators had previously filed another warrant to search the home of one the men Lonczak was with before she died. The man told police he had been out with Lonczak drinking beer and smoking marijuana on Aug. 21, according to the warrant. He told police he then brought Lonczak back to his Vienna-area home.

Lonczak remained at his house for a few hours before leaving on foot, the man said. On Aug. 23, a police bloodhound tracked Lonczak’s scent to an area behind the home, where her body was found, according to the search warrant.

Fairfax County police had previously said narcotics might be a factor in Lonczak’s death. They are still awaiting the medical examiner’s determination of how she died.

Officers found Lonczak’s body on the morning of Aug. 23 in the 8200 block of Madrillon Estates Drive, police said. Police initially said Lonczak had been reported as a runaway but later said she was voluntarily in the company of people she knew before she died.