This is first such confession made by security forces in the state.
16-year-old Zahid Farooq was killed when BSF opened fire on a group of people in Nishat area of Srinagar.
BSF has identified one of its personnel involved in the killing.
According to source, the BSF will be handing over the soldier to Jammu Kashmir police for conducting the test identification parade.
This development comes after Chief Minister Omar Abdullah raised the issue of Zahid's killing with the Centre at the recent Conference on Internal Security.