A truck and a so-called TMA vehicle were reportedly involved in the accident, which occurred west of Örebro just before 8 a.m. on Wednesday.
A large amount of debris ended up on the roadway and traffic has been halted. This morning, the police said the road will remain closed for several hours and advised motorists to use county road 691 instead.
According to the police, several motorists have turned around on the E18 because of the closure.
"Behavior like this is completely unacceptable and the risk of an accident occurring is very high," the police wrote on their website.
The police have opened an investigation into gross negligence in traffic and causing bodily harm. A man has been arrested.
