Gera (dpa/th) - Four people were injured in a car accident in Gera, some seriously. A 24-year-old driver left the road when turning on Sunday afternoon, the police said on Monday. His vehicle collided head-on with a tree. The driver was slightly injured in the impact. His three passengers aged 18, 22 and 24 were seriously injured. The accident area was completely closed off during the accident investigation and the car was towed away. The cause of the accident is still unknown. The investigations are ongoing.