BERLIN (Reuters) - A German driver who rammed a crowd of shoppers in Heidelberg, killing one man and injuring two others, has no apparent link to terrorism and has refused to answer questions about the incident, police said on Sunday.

The 35-year-old suspect, who was chased and shot by police and later operated on in a hospital in the southwestern German city for his wounds, has been formally arrested, a joint statement by police and the public prosecutor said.

On Saturday evening, local police issued a denial by Twitter that the man had a migrant background after a wave of tweets from Germany and abroad claimed he was a refugee and that officials were not admitting this.

Germany has taken in over a million migrants in the past 18 months and reports of crime among them have alarmed voters.

The victim was a 73-year-old German man, while the two injured people were an Austrian man, 32, and his Bosnian female partner, 29, the statement said.

“Based on investigations so far, there are no signs of a terrorist or extremist motive for the crime,” it said. “During his first interrogation, (the suspect) made no response to the accusations.”

According to the statement, the suspect apparently fled the scene with a kitchen knife in hand. When police cornered him a few blocks away, he ignored their orders to drop the knife and turned on them. After pepper spray did not stop him, an officer shot him in the stomach, wounding him seriously.

He underwent an emergency operation in a Heidelberg hospital and is now out of danger.

Authorities are investigating whether the suspect might be classified as having diminished responsibility, the statement said, but added: “But there are so far no indications of this”. The man had no previous police record.

The incident caused a storm of comments on social media, with several claiming the suspect was a refugee or a Muslim and accusing the police of withholding information on him.

After refuting several misleading tweets about the suspect, local police tweeted: “And once again for everyone: suspect German WITHOUT migrant background”

The local Rhein-Neckar-Zeitung newspaper said the suspect had stopped at a red traffic light and when it turned green put his foot down before hitting the group of people at high speed and smashing into a pillar.

German authorities are on high alert after a failed Tunisian asylum seeker drove a truck into a Christmas market in Berlin on Dec. 19, killing 12 people.