Several passengers have been injured in a 18-vehicle pile-up in Bolu tunnel on March 19. The accident involved minibuses, cars and trucks, Trend reports citing Hurriyet Daily News.
Some 17 people were injured in the accident, according to Health Minister Fahrettin Koca.
Following the accident, the highway connecting Istanbul and Ankara was closed to traffic on Istanbul direction.
Emergency teams were dispatched to area.