Swedish police have confirmed they discovered a suspect device inside the lorry which was driven into a Stockholm department store on Friday.
The “technical device” was found in the driver’s seat of the vehicle, National Police Commissioner Dan Eliasson said.
Mr Eliasson also said the suspect in custody was from Uzbekistan, 39, and known to security services.
Friday’s attack saw a hijacked lorry driven into Ahlens department store on Drottninggatan (Queen Street).
Four people were killed – 10 remain in hospital, including a child. Two are in intensive care.
Eyewitnesses: Lorry was ‘trying to hit people’
What do we know about the suspect?
The suspect, who was not named, was known to the security services.
However, he had only been seen as a “marginal character”, Mr Eliasson said.
The head of Swedish security police, Anders Thornberg, said the suspect had not been “part of any of the security police’s ongoing investigations”, but was “a person who has previously figured in our intelligence flow”.
Mr Eliasson said police had reason to believe the suspect was the man behind the attack.
“Nothing points to the fact that we have the wrong person, on the contrary suspicions have strengthened as the investigation has progressed.”
“We still cannot rule out that more people are involved.”
Was there a bomb in the lorry?
Police say it is too early to tell what the device in the lorry was – only that “it should not be there”.
“I cannot say at this stage that this is a bomb or some sort of flammable material,” Mr Eliasson said.
“We are doing a technical investigation.”
What is the Swedish government doing?
Swedish Prime Minister Stefan Lofven has called it a terrorist attack, with borders tightened at his request.
“It is way too early to draw some political conclusions from all this. This is a moment for sorrow; for grief,” he said.
“We’re also determined to continue to be an open society; a democratic society.
“And that is something I am totally confident the Swedish people also feel.”
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