Berlin police have published a picture of a 21-year-old man suspected of carrying out Saturday night’s attack at the celebration in which a vehicle rammed into a crowd, killing one person and injuring more than a dozen.

In yesterday’s online post, police urged members of the public to help them find the man identified as Abdul B, adding that it was not clear whether he acted alone. They said more than one person may have got out of the vehicle after it came to a halt close to the city’s Brandenburg Gate.

Three of the 16 people who were injured in the attack were in a life-threatening condition, and some of the injuries included stab wounds, police and emergency services said.

Investigators believe that the attack was motivated by Islamist ideology, Germany’s interior minister said.

Police described the wanted man as slim, around 1.90 metres tall, with black hair, and last seen wearing a black hooded top and white trousers.

“Who can share anything about his current whereabouts?” the statement said.