One person died and 17 were injured, some critically, after a van drove into a crowd near a large public festival in central Berlin on Saturday evening, German police said.
Authorities launched a manhunt after the apparent attack, which took place in the city's Tiergarten park near the Brandenburg Gate. Hours later, police said they had identified an Islamist extremist as a suspect and were seeking his arrest.
"According to our latest information, the vehicle drove into the Tiergarten around 10pm, injuring several people in the process, and then came to a standstill after hitting a tree," a police representative at the scene said.
"The vehicle was empty, which is why we are currently working intensively to track down the perpetrator or perpetrators."
A fire brigade official said eight of the injured suffered serious wounds, including three whose lives were at risk.
Police said the suspected perpetrator had not yet been arrested but was known to authorities as a member of the Islamist scene in Berlin.
German tabloid Bild quoted a witness as saying a man got out of the van and fled on foot.
Hundreds of thousands of people had gathered in the German capital for a major annual festival before the incident brought celebrations to an abrupt end.
Large numbers of emergency personnel were sent to the area as investigators worked to establish the circumstances of the attack.
"This is one of the worst days for our community and a day I hoped I would never have to experience. I'm shocked," Julian Miethig, a visitor, said.
The festival is one of Berlin's largest annual public events and regularly attracts hundreds of thousands of participants. It combines a parade with calls for equality, inclusion and protection against discrimination.
