RAF MILDENHALL, England — A memorial service will be held Friday for two England-based airmen killed in a car crash last week.

The ceremony will be held at 9 a.m. at RAF Lakenheath’s base chapel for Staff Sgt. Mark Stephany, 24, and Senior Airman Daniel Addabbo, 23, both assigned to the 48th Maintenance Squadron.

Stephany and Addabbo were killed at about 7:30 p.m. May 30 on a road near Lakenheath when their vehicle collided head-on with another car. Two other airmen in the victims’ vehicle were treated for minor injuries. The passenger and driver of the other car were taken to the hospital. Authorities said this week it is unclear what caused the collision.