The 16-year-old boy was taken into custody from his house in Aman Vihar area of West Delhi after the assault was confirmed in the medical report of the victim.
"The minor girl was alone at her home when the accused barged and sexually assaulted her and fled the spot yesterday evening.
"The girl later informed her father, who is a labourer, about the incident. He lodged a complaint and the girl was shifted to hospital," said a senior police officer.