A truck has crashed into the Ahlens department store in central Stockholm. Picture: AFP/TT News Agency/Andreas Schyman

A hijacked truck was rammed through a crowd in central Stockholm killing at least four people shortly after 2pm local time yesterday.

A further 12 were injured when the truck mowed down pedestrians and then crashed into a department store.

A man was arrested in the suburb of Marsta, close to the city’s international airport, on Friday (local time) after the Swedish police released a grainy image of a person they said was a person of interest.

Swedish media outlet Aftonbladet is reporting that the man confessed to carrying out the shocking attack, citing several unnamed sources. Police, however, have declined to comment on this officially.

A second mand was then arrested in the northern suburb of Hjulsta. According to Swedish public broadcaster SVT, the second man is said to be connected to the first man who was arrested.

Before the two arrests were made, Swedish police said they were interviewing two other people in relation to the deadly truck attack.

“I can confirm that we have taken in two people for questioning, but that does not necessary means that they are suspects,” police spokesman Lars Bystrom said on Friday.

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.”

A beer truck has crashed into a department store in Stockholm, Sweden.Source:Supplied

Multiple European news outlets have put the death toll at five, but Stockholm police spokesman put the figure at four.

Police arrested this man in relation the Stockholm truck attack. Picture: AFP/Stockholm PoliceSource:AFP

The truck incident killed and injured several people in Stockholm. Picture: AFP/Stockholm PoliceSource:AFP

Three armed men jumped out of the truck during the incident, according to Swedish media outlet Expressen.

Police cordon the truck that crashed into the Ahlens department store at Drottninggatan in central Stockholm. Picture: AFP/Jonathan NackstrandSource:AFP

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.

Forensic agents move one of the bodies at the scene where a truck crashed into the Ahlens department store at Drottninggatan in central Stockholm. Picture: AFP/Jonathan NackstrandSource:AFP

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.”

An injured person on the ground is helped after a truck crashed into a department store injuring several people in central Stockholm, Sweden. Picture: Rose-Marie Otter/ TT News Agency via APSource:AP

Another witness named Anna said she “saw hundreds of people run, they ran for their lives”.

“I turned and ran as well,” she said.

Police officers work at the scene where a truck crashed into the Ahlens department store at Drottninggatan in central Stockholm. Picture: AFP/Jonathan NackstrandSource:AFP

Police officers at the scene where a truck crashed into the Ahlens department store. Picture: AFP/TT News Agency/Noella JohanssonSource:AFP

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.

People react at the scene where a truck crashed into the Ahlens department store at Drottninggatan in central Stockholm. Picture: AFP/ Jonathan NackstrandSource:AFP

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.

A body, centre at right, lies on the ground on at the scene after a truck crashed into a department store injuring several people in central Stockholm, Sweden. Picture: Andreas Schyman, TT News Agency via APSource:AP

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.

Emergency personnel load a person into an ambulance after a truck crashed into a department store injuring several people. Picture: TT News Agency via APSource:AP

— with wires