In the collision of a car with a truck on the A7 near Schnelsen, three people were injured on Saturday night.
The 50-year-old driver of the car suffered serious injuries, a fire department spokesman said on Saturday morning.
The 29-year-old passenger and a child in the back seat were therefore slightly injured.
The truck driver was uninjured.
Hamburg - When driving onto the A7, for an initially unexplained cause, the car ran into the sward next to the road, began to lurch and then collided with the truck, which, according to initial findings, was driving on the median.
The driver and passenger were trapped and had to be freed by the emergency services.
All car occupants were taken to the hospital by ambulance.
The Autobahn 7 was completely closed for several hours in the direction of travel south.
dpa