At least five people are dead and many more injured after a terror attack which saw a hijacked lorry plough into pedestrians in Stockholm.
Swedish Prime Minister Stefan Lofven said it appeared the crash was "a terror attack" and the country's intelligence service said there was "a large number of injured".
Mr Lofven said a suspect had been arrested in connection with the attack.
Blood stains were visible on the streets along with bodies covered in blankets in the aftermath of the incident.
Paramedics could also be seen tending to the injured near the lorry, which was embedded in the corner of a shopping mall with its cab burning.
The incident was in Drottninggatan, a street in a busy shopping district in the centre of the Swedish capital.
The attack comes after trucks were used in terror attacks in Nice and Berlin last year and just two weeks after Muslim convert Khalid Masood ploughed his car into pedestrians on Westminster Bridge in London.
Swedish broadcaster SVT reported that at least five people had been killed but police could not immediately confirm.
The Aftonbladet newspaper reported that the truck had been hijacked from Swedish beermaker Spendrups earlier on Friday.
The lorry ploughed into the Ahlens department store which is part of a country-wide chain.
Witness Jan Granroth told Aftonbladet that "we stood inside a shoe store and heard something ... and then people started to scream." He said: "I looked out of the store and saw a big truck."
Another witness quoted by the paper said: "When I came out I saw a lorry standing there, with smoke coming from it, and there were loads of bits of cars and broken flower pots along the street."
Another witness said: "People are lying mowed down along the whole route. CPR is being given and rubbish bags are being used to cover the lifeless bodies."
The crash is close to the scene of a terror attack in 2010 when Taimour Abdulwahab, a Swedish citizen who lived in Luton, blew himself up.
The terrorist, who police concluded acted alone, died on December 11 2010 in the Bryggargatan area. No-one else was killed.
Abdulwahab rigged an Audi car with explosives in the hope that the blast would drive people to Drottninggatan, a busy shopping street, where he was waiting to set off two more devices strapped to his chest and back.
The car bomb never went off and, after setting fire to the Audi, he was unable to detonate the other two explosives as planned.
He made his way down a side street off Drottninggatan and, in an apparent attempt to fix the faulty trigger up his sleeve, set off the bomb on the front of his body, killing only himself.
British national Itay Lotem was nearby when the lorry ploughed into pedestrians in the centre of the city.
"I was sitting in a cafe, I just suddenly saw people coming in and talking about a lorry that had driven into people," he told BBC News.
"I walked out and there were many people in that street, it's a pedestrian street.
"Very quickly police cordoned everything off."
Office worker JP Hanson described the scene as mayhem and said his building has been put into lockdown.
"Right now, inside here we have maybe 40 people," he told BBC News.
"The mood is quite positive, obviously people are afraid - but I would say it's a strong mood."
Arash Pendari was in an office overlooking Drottninggatan when he realised panic was unfolding in the street below.
The 34-year-old said: "Some of my co-workers heard something outside and I started moving towards the window. I followed them towards the window and I saw a crowd of people moving away from the shopping centre, quickly running.
"Security were there and police were there quickly moving everybody away from the area.
"Then we started looking out and saw the fire trucks coming, the police cars coming, people driving out of the area quickly, honking and so on."
He added that the surrounding shops were evacuated shortly afterwards and he was told to stay in the office.