Police say Alexander Buckley offered several reasons why a smartphone belonging to a teenager fatally shot hours earlier was hidden in a shoe in his bedroom closet.

It was his girlfriend’s, court documents say he first told detectives who interviewed him. He bought it for $40 from a man on the street, he said next. Then, according to the records, he saw Siobhan Nicole Lee, 18, dead on a sidewalk in Northwest Washington and found the phone next to her body.

Police say Buckley, 21, met Lee through a social media app and that she was killed during an early morning encounter on Friday at Fifth and Nicholson streets in Brightwood. Police said Buckley lived three blocks from the shooting scene.

Documents filed over the weekend in D.C. Superior Court detail the circumstances that police say drew Lee to a District street corner at 2:30 a.m. The Takoma Park teen arrived there after work at a Silver Spring grocery store where she staffed a Starbucks stand, and she died of a gunshot wound to the head.

Police say in the charging documents that Lee and Buckley had chatted via text messages on Friday, but had never met. Details of the shooting remain unclear, but police said that in addition to Lee’s phone, they found a Ruger 9mm semiautomatic handgun in Buckley’s apartment. They did not say whether that gun was used in the shooting.

A judge on Saturday ordered Buckley held on a charge of second-degree murder while armed. A preliminary hearing is scheduled for Feb. 8.

Buckley’s court-appointed attorney from the Public Defender’s Office did not return a call seeking comment Monday.

Lee told a friend early last week that she had met a man on the Internet and asked for directions to the 500 block of Missouri Ave. NW, about three blocks from where Buckley lived, according to court documents.

Police also used data from a wireless service provider to track Lee’s phone to Buckley’s building, according to court documents. Police said Buckley pointed detectives to his closet when questioned about the phone.

But police said Buckley gave them several explanations and at first denied knowing Lee or exchanging messages with her, despite what court documents called an extensive log of calls and texts.

After several rounds of interviews, police said they showed Buckley a photograph of Lee and he admitted recognizing her. His final explanation, according to the charging documents, was that he was at a bus stop with Lee and that he had asked her to have sex and she told him she had to work.

Buckley told police he then hugged Lee and walked a block to meet a man known as “Junkie” who owed him $10. The court documents say he told detectives that he heard a gunshot and saw a man run away, then “ran to the decedent and observed [her] unconscious and he took her iPhone.”