A Vienna man admitted in court Monday that he tried to hide the body of a 16-year-old McLean girl who had overdosed on heroin by stashing it in some bushes and covering it with a window screen, authorities said.

Kyle Alifom, 20, pleaded guilty to a federal charge of tampering with evidence, admitting that he tried to hide the body of Emylee Lonczak after the girl had fatally overdosed. He is the first to admit wrongdoing in her death, though he was not the person who either sold her the deadly drug or injected her with it.

The case, in many ways, epitomizes what authorities say is a disturbing increase in heroin use, especially among young people and other novice buyers who do not recognize how addictive and lethal the drug can be. Court filings say that the night Lonczak died was the first time she had used heroin intravenously, and someone else had to inject it into her arm because she could not find a vein.

Lonczak, a student at McLean High School, has been remembered by her former soccer coach as a quiet, respectful girl who was “always trying to get in the game.”

According to documents filed in U.S. District Court in Alexandria, Alifom admitted that he, Lonczak and two others — who are not identified in court papers — drove from Virginia to Washington on Aug. 21 to buy heroin and that they used it sitting in their vehicle. Another person in the vehicle — not Alifom — injected Lonczak’s arm when she could not, according to the documents.

Lonczak soon fell unconscious in the back seat of the vehicle, and Alifom and another person in the group took her to Alifom’s house and put her on a bed in the basement, according to the documents. The documents say that Alifom discovered her dead when he woke up the next morning, so he dragged her body to some bushes behind a neighbor’s house and left it there, covered with an abandoned window screen.

Earlier court filings say Alifom was concerned about getting in trouble because he was on probation for other offenses. Fairfax County police found Lonczak’s body on Aug. 23.

Alifom had initially been charged with knowing that heroin was distributed resulting in a death and assisting the offender to hinder his apprehension, trial and punishment. His attorney, Kevin Brehm, wrote in court papers that Alifom was accused of being an “accessory after the fact,” noting that Alifom did not sell or give Lonczak any drugs.

Brehm said Monday that he and prosecutors agreed that the tampering charge “made the most sense,” though it was too early to say what impact it would have on Alifom’s sentence.

Authorities said the tampering charge carries a 20-year maximum sentence and the earlier charge carries a 15-year maximum sentence. Those terms, though, do not necessarily reflect what Alifom will receive, as sentences in the federal system are guided by a sophisticated process in which court officials consider the nature of the offense, the defendant’s history and other factors.

Alifom is scheduled to be sentenced May 16, authorities said.

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