There was no immediate confirmation about whether it was a terror attack.
A vehicle ploughed into a group of people in the western German city of Muenster on Saturday, killing several of them while the driver shot himself, police said.
German news agencies said a car had hit bystanders in the western city.
Police confirmed there had been several casualties but has not yet specified the toll or given any details about the incident.
'There are deaths and injured. Please avoid the area, we are on scene,' the regional police service said on Twitter.
The driver of the vehicle has killed himself, agencies quoted police as saying.
"The driver shot himself," a police spokeswoman was quoted.
Police also urged people to avoid 'speculation' about the incident.
According to the online edition of Spiegel, authorities were 'assuming' the incident was an attack, though there was no immediate official confirmation.
Photograph: Kind courtesy @joshdcaplan/Twitter
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