A truck rammed into a departmental store in central Stockholm killing at least 3 people and injuring several as the Swedish PM called it a terror attack Photograph: (WION)
One person has been arrested in connection with the attack, police said. There was no immediate claim of responsibility
A massive manhunt was underway for the driver of a stolen truck that ploughed into a crowd outside a busy department store in central Stockholm Friday, killing four and injuring 15, Swedish police said.
A national police chief, Stefan Hector, said the police's "working hypothesis is that this is a terror attack".
One man was arrested in connection with the attack but the driver remained at large, police said.
According to the Aftonbladet newspaper, the arrested man is a 39-year-old of Uzbek origin and a supporter of the Islamic State (IS) group.
Prime Minister Stefan Lofven said he had strengthened the country's border controls.
"Terrorists want us to be afraid, want us to change our behaviour, want us to not live our lives normally, but that is what we're going to do. So terrorists can never defeat Sweden, never," he said.
If confirmed as a terror attack, it would be Sweden's first such attack with a deadly outcome.
There was no immediate claim of responsibility.
Part of central Stockholm was cordoned off and the area was evacuated, including the main train station. All subway traffic was halted on orders from the police.
Stockholm's subway service has now been cleared to restart after the attack, but all bus traffic in the centre of the city remains at a standstill, the public transport authority said.
The authority said trains would not stop at the two stations closest to where the truck attack took place.
"A truck that drove into a crowd of people outside a busy department store in central Stockholm was a deliberate attack," Swedish intelligence agency Sapo said.
"We were standing by the traffic lights at Drottninggatan (Queen Street) and then we heard some screaming and saw a truck coming," a witness, who declined to be named, told Reuters.
"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 tire. It was terrible to see," said the man, who saw the incident from inside his car.
Radio Sweden reporter Martin Svenningsen said he saw three dead people "but probably more". A Reuters witness saw a number of body-like forms covered by blankets at the scene.
A truck rammed into a departmental store in central Stockholm killing at least 3 people and injuring several as the Swedish PM called it a terror attack (WION)
"Police received a call from SOS Alarm that a person in a vehicle has injured other people on Drottninggatan," police wrote on Twitter.
Thick smoke was rising from the scene, but police have yet to confirm the information. Video images showed an area blocked off by police and crowds gathering around the police cordon.
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.
King Carl Gustaf, Sweden's head of state, expressed his horror at the attack.
"Our thoughts are going out to those that were affected, and to their families," he said in a statement from the royal palace.
European leaders reacted almost immediately with German Chancellor Angela Merkel declaring her support for the Swedish people.
"Germany stands with Sweden against terror," German Chancellor Angela Merkel's spokesman said.
Jean-Claude Juncker, president of the European Commission said,"Sweden truck attack is an attack on us all." "One of Europe's most vibrant and colourful cities appears to have been struck by those wishing it – and our very way of life – harm," he said.
UN Secretary General Antonio Guterres joined other leaders to condemn the attack. Guterres expressed hope that those responsible for the attack are swiftly brought to justice.
A truck drove into a crowd in Stockholm (Agencies)
An area of central Stockholm was cordoned off and large numbers of police and emergency services were at the scene. The area was evacuated. (Reuters)
Several attacks in which trucks or cars have driven into crowds have taken place in Europe in the past year. Al-Qaida in 2010 urged its followers to use trucks as a weapon.
In London on March 22, a man in a car killed pedestrians on Westminster Bridge, killing four, and then stabbed a policeman to death before being shot by police.
Islamic State claimed responsibility for two attacks - Nice, France, July 2016, when a truck killed 86 people celebrating Bastille Day, and one in Berlin in December last year, when a truck smashed through a Christmas market, killing 12 people.
(WION with AFP, Reuters & other agency inputs)