A Rockland County teen was killed yesterday morning after an accident on the Thruway in Clarkstown. New York State Police say 19 year-old Rashid Hopson of Spring Valley was pronounced dead at the scene by Rockland’s Medical Examiner after the car in which he was a back seat passenger struck another car on I-87 northbound. Police say a Honda Accord was driven by 18 year-old Alon Forbes of the Bronx. He struck the rear of a Suburu Outback driven by 59 year-old Terri Kugler of Hawthorne, New Jersey. Kugler was not injured, but 18 year-old Ashawn Duncan of Spring Valley, the front seat passenger of the Honda, was reported to be in critical condition at Nyack Hospital. Three others suffered minor injuries and were treated and released. The crash is under investigation.