POLICE have arrested a man after a hijacked truck was rammed through a crowd in Sweden, killing at least four.
A further 12 were injured when the truck mowed down pedestrians and crashed into a department store in central Stockholm, Sweden.
Images from the scene show people running for their lives outside the up-market Ahlens department store on Drottninggatan, which is the biggest pedestrian street in the Swedish capital and above the city's central subway station.
Swedish Prime Minister Stefan Lofven says everything indicates this is a "terror attack".
"Sweden has been attacked," he said. "This indicates that it is an act of terror."
Multiple European news outlets have put the death toll at five, but Stockholm police spokesman put the figure at four.
Watching the events unfold after a truck drove into Åhléns on Drottninggatan. pic.twitter.com/kxJLUOAsns— Emil Stenqvist (@svammel) April 7, 2017
Stockholm police have released CCTV images of a man wanted in connection to the truck crash. Officers were also seen pinning a man down after the attack.
It's is not clear if either of these men is the one police say they have arrested.
Three armed men jumped out of the truck during the incident, according to Swedish media outlet Expressen.
A witness inside a car, who declined to be named, heard screaming as the truck approached.
"Then it drove into a pillar at Ahlens City (department store) where the hood started burning. When it stopped we saw a man lying under the tyre. It was terrible to see," the man told Reuters.
Other witnesses told Aftonbladet of hundreds of shoppers ran away in panic.
"We stood inside a shoe store and heard something ... and then people started to scream," witness Jan Granroth said.
"I looked out of the store and saw a big truck."
Another witness named Anna said she "saw hundreds of people run, they ran for their lives".
"I turned and ran as well," she said.
A man named Dimitris said two people were run over in the chaos.
"I went to the main street when a big truck came out of nowhere," he said.
"I could not see if anyone was driving it but it got out of control. I saw at least two being run over.
"I ran as fast as I could."
The usually busy pedestrian mall has been locked down by police and citizens have been urged to avoid the area.
Stockholm locals have posted confronting images and videos on social media, some that show streets smeared with blood and strewn with covered bodies covered.
Emergency services have also been filmed spraying foam on the truck.
Swedish broadcaster SVT said shots were fired at the scene and the Swedish news agency TT said several people were rushed away in ambulances.
Thick smoke could be seen on the streets, while video showed an area blocked off by police and crowds gathering around the police cordon, according to AFP.
Helicopters could be heard hovering in the sky over central Stockholm, and a large number of police cars and ambulances were dispatched to the scene, witnesses said.
While Islamic State has not claimed responsibility for the crash, it has the hallmarks of other attacks carried out by the terror organisation's supporters.
In London six people, including the attacker died, after Khalid Masood drove a car onto Westminster Bridge hitting pedestrians in late March.
A similar incident occurred in Nice, France, last July killing 86 people, while another truck attack killed 12 at a Christmas market in Berlin in December.
In a statement, Swedish police said they could not exclude that the Stockholm incident was an act of terror based on other events in Europe.
- with wires
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