EASTON - Students at Joel Barlow High School are mourning the death of a fellow student who was killed in an ATV crash in Easton Saturday.

Officials say Robert Smuniewski, 18, was killed when he was thrown from his ATV after colliding with a car along Sport Hill Road early Saturday morning.

Officers say the car was driven by an 84-year-old Bridgeport resident.

Investigators say it appears the car struck Smuniewski from behind, but they're still trying to figure out if the teen was riding the ATV or pushing it from behind.

School officials say Smuniewski's classmates honored him at school today by dressing up.

VIDEO: Fatal ATV crash Teen killed in ATV accident in Easton