Police say a 10-year-old boy has been arrested for bringing a handgun into a Westchester Catholic school.

Investigators say the fourth-grader at St. Eugene's Catholic School on Tuckahoe Road in Yonkers had the gun in his backpack and showed it to another student - even making a threat.

Parents say the student was just trying to show off by displaying his father's handgun inside his backpack last Thursday, but when he returned to school on Monday, he handed another classmate a threatening note for telling on him.

According to a mother whose child is a student at the school, the principal never informed other parents or called authorities immediately after learning about the gun.

Police say the young suspect turned himself in today with his parents and was booked on menacing and harassment charges.