A man armed with a knife has attacked passengers on a bus in the northern German city of Lübeck, wounding several people, one seriously, police say.
A 34-year-old local man was arrested and taken into custody. Police said there was no indication the suspect had been politically radicalised.
They said on Twitter that 10 people were known to have been hurt. Local media reports put the number at 14.
An area around a bus stop in the city's Kücknitz neighbourhood was sealed off.
Police said a smoking backpack was found in the bus, containing a "fire accelerant" but no explosives.
"The exact number of injured is still unclear. There were no dead," police said in a statement. "The background to the crime is still unclear and is the subject of the ongoing investigation."
The statement added: "The identity of the perpetrator has been clarified: a 34-year-old German citizen resident in Lübeck. There are currently no indications the man was political radicalised and no signs of a terrorist background."
The attack took place at 13:47 local time (11:47 GMT). An eyewitness told the local Lübecker Nachrichten newspaper that a passenger had just given up his seat for an older woman, when the attacker stabbed him in the chest.
The bus driver pulled over to the side of the road and passengers fled. Police said the suspect was overpowered by officers at the scene.
In April, a man drove a camper van into a group of people outside a restaurant in the German city of Münster, killing two people before shooting himself dead.
Police said there was no link to terrorism in that case.
In Berlin in December 2016, a Tunisian who had links to Islamist militants hijacked a truck and ploughed into a Christmas marketplace, killing 12 people.