Tributes have been left near the scene where five people were killed when a driver hit pedestrians at high speed in the Germany city of Trier.

Lit candles and flowers have been placed at the base of the city’s Roman gate as residents mourn those killed alongside more than a dozen injured in the incident on Tuesday afternoon.

Speaking near the makeshift memorial, city mayor Wolfram Leibe said: “The victims and their families need answers.”

A 51-year-old local man arrested at the scene has made a statement to authorities and remains in custody as he is investigated for five counts of murder, 18 counts of attempted murder and causing bodily harm, prosecutor Peter Fritzen said.

Trier incident
Police at the scene of the incident in Trier, Germany (Michael Probst/AP)

Authorities do not believe the suspect drove into the pedestrians for any political, religious or similar reason, but they have not yet been able to determine a motive, Mr Fritzen added.

Statements the suspect made to police immediately after his arrest kept changing and were “partially incomprehensible”, the prosecutor said.

“The suspect also showed psychological abnormalities in his behaviour during and after his arrest and in police custody.”

A comprehensive psychological examination has been ordered.

The man had been drinking heavily before the attack, Mr Fritzen said, and questioning will continue over the next few days.

Among the five killed were a 45-year-old man and his nine-week-old daughter. His wife and one-year-old son are among the injured and are being treated in a hospital, police said.

Trier incident
The incident occurred in a pedestrian area of the city on Tuesday afternoon (Michael Probst/AP)

The others killed were three women aged 25, 52 and 73.

Police received the first call about the attack just before 1.50pm and apprehended the suspect four minutes later.

Zig-zagging through the pedestrian zone, police said the driver travelled about 800 metres in total, “leaving behind him a trail of dead, injured and rubble”.