An autonomous test vehicle was involved in the serious accident with one dead and nine seriously injured on the B28.

Whether the vehicle was driven by the 43-year-old driver or not is the subject of the investigation and currently unknown, a police spokesman said on Tuesday.

The cause of the accident is still unclear.

The 43-year-old was driving an e-test vehicle for autonomous driving near Römerstein (Reutlingen district) on Monday afternoon.

In a curve, the car came into the oncoming lane for reasons that are still unclear and grazed an oncoming car there.

The 70-year-old driver then crashed his car head-on into the car of a 32-year-old.

The man's car left the roadway and immediately caught fire.

In the further course, the E-test car also crashed head-on into another car.

The 33-year-old passenger in the car suffered fatal injuries from the violent impact.

According to the police, there were two men aged 31 and 47 in the 43-year-old's car, as well as a 42-year-old and a one-and-a-half-year-old child.

They were seriously injured, as were the other drivers and a 33-year-old passenger in the 32-year-old's car.

They were taken to clinics.

The Tübingen traffic police have started investigations together with an expert.

The rescue service was on site with four rescue helicopters and ten ambulances.

In addition, 80 firefighters with 15 emergency vehicles moved out.

The federal highway 28 was completely blocked for several hours as a result of the accident.

The police estimate the damage to the vehicles involved at around 180,000 euros.