A 19-year-old man accused of the first-degree murder of his 6-year-old nephew is scheduled to be arraigned on Tuesday afternoon.

Charging documents were filed on Friday in relation to the Oct. 16 incident.

According to the documents, Andrew Henckel told detectives on Oct. 17 that he drowned his nephew, Dayvid Pakko, in a bathtub on the night of Oct. 16, when the boy’s mother and her live-in boyfriend were both out of their Lynnwood apartment. Henckel told officers he “wasn’t really thinking” at the time and “just kinda did it.” He did not provide a reason why when asked.

Henckel later detailed cleaning up water from the bathroom using towels on the racks and that his cell phone stopped working after getting wet, as it was in his pocket at the time. Detectives confirmed the phone had sustained water damage.

Henckel, who lives in Texas, was at his sister’s Lynnwood residence for a visit. He had been at the apartment since Oct. 8 and was planning to stay for another five weeks or so.

Earlier on Oct. 16, Henckel told officers he remembered spending time with Pakko, watching television and playing with Legos, while the boy was home sick from school. Pakko was a first grader at Beverly Elementary.

Henckel told detectives this was not the first time he was left alone with Pakko and that he didn’t have any problems with his nephew.

When he first spoke to officers on the night of Oct. 16, Henckel said he was sleeping when Pakko went missing. After officers discovered Pakko’s body inside a nearby dumpster, Henckel told them he drowned him. On Oct. 25, the Snohomish County Medical Examiner confirmed Pakko’s cause of death to be drowning.