In a rear-end collision on Autobahn 7, the driver of a van was seriously injured on Wednesday evening.
According to an emergency doctor, there is probably mortal danger, said a police spokeswoman.
The accident happened between the Laatzen junction and the Wülferode service station in the direction of Hamburg.
The van was said to have driven onto a tractor-trailer.
Hanover - Further information - such as the identity of the seriously injured person - was not yet available.
dpa