On Friday evening, a man ploughed a car into a crowd of shoppers at a Christmas market in the German city of Magdeburg.
The attack has left five people dead and more than 200 injured, with many in a critical condition.
One man has been arrested over the attack, and police believe he was solely responsible.
How did the attack unfold?
Unverified footage on social media showed a black BMW travelling at high speed through the pedestrian walkway between Christmas stalls.
Eyewitnesses described jumping out of the car’s path, fleeing or hiding. One told Reuters news agency that police were already at the venue and chased after the car.
Later footage showed armed police confronting and arresting a man who can be seen lying on the ground next to a stationary vehicle – a black BMW with significant damage to its front bumper and windscreen.
BBC correspondent Damien McGuinness in Magdeburg said the market was surrounded by concrete blocks. However, there was a gap for pedestrians to go through, but also wide enough for a car.
Who are the victims?
Five people have been confirmed to have died in the attack, one of whom is a child.
More than 200 people have been injured and at least 41 are in a critical condition.
The toll had earlier been reported as two dead and 68 injured, but was revised to the much higher totals on Saturday morning.
None of the victims has been identified yet.
Who is the suspect?
German media has identified the suspect as Taleb A, a psychiatrist who lives in Bernburg, around 40km (25 miles) south of Magdeburg.
The motive behind the attack remains unclear, but authorities have reported that they believe he carried out the attack alone.
Originally from Saudi Arabia, he arrived in Germany in 2006 and in 2016 was recognised as a refugee.
Evidenced by social media posts, the suspect is an outspoken critic of Islam, and has promoted conspiracy theories regarding an alleged plot by German authorities to islamicise Europe.
A report from Der Spiegel said a complaint was filed against Taleb A with the authorities a year ago over statements which officials concluded did not constitute a concrete threat.
What have officials said about the attack?
“The reports from Magdeburg raise the worst fears,” the German chancellor, Olaf Scholz, said on social media platform X.
Magdeburg’s city councillor for public order, Ronni Krug, said the Christmas market will stay closed and that “Christmas in Magdeburg is over”, according to German public broadcaster MDR.
That sentiment was echoed on the market’s website, which in the wake of the attack featured only a black screen with words of mourning, announcing that the market was over.
The Saudi government expressed “solidarity with the German people and the families of the victims”, in a statement on X, and “affirmed its rejection of violence”.
UK Prime Minister Sir Keir Starmer said he was “horrified by the atrocious attack in Magdeburg”, adding that his thoughts were with “the victims, their families and all those affected” in a post on X on Friday night.