A man arrested following the deadly lorry attack in Stockholm is "likely" to be the driver of the hijacked truck which ploughed into pedestrians, Swedish Police said.
The man was detained in a northern Stockholm suburb on Friday and later arrested on suspicion of "terrorist crimes through murder".
Four people were killed after the beer lorry crashed into a department store in the Swedish capital on Friday afternoon.
"Yes, it is correct, it is likely him," police spokesman Lars Bystrom said on Saturday.
"The person in question has been arrested as the culprit, in this case the driver," he added.
The prosecutor, Hans Ihrman, said that the unidentified suspect should face a pre-trial custody hearing before midday on Tuesday or be released.
Officials also confirmed that only one person has been arrested in the case, contrary to media reports that two had been detained.
Beauty products remain on display yards from where a department store shop window was smashed in during Friday's deadly lorry attack in Stockholm city centre.
Swedish police have cordoned off the attack site and towed the vehicle away as an investigation gets underway.
Four people were killed after the hijacked lorry was driven along the pedestrianised street, Drottninggatan, in the busy shopping district before crashing into the Ahlens department store just before 3pm local time.
The lorry used in the suspected terror attack in Stockholm has been towed away from the central shopping street.
Swedish police said cordons around the crime scene would remain in place until the on-site investigation has been completed.
The first man arrested in connection with Stockholm's lorry attack is being held "on suspicion of terrorist crimes through murder", the office of the Swedish prosecutor has said.
It is the strongest degree of suspicion in Sweden's legal system, which can apply several different levels to hold a person.
Police confirmed he was now under "prolonged arrest".
The Stockholm lorry attack bears similarities to recent terror attacks in Westminster, Berlin and Nice.Read the full story ›
A second man has been arrested in relation to the deadly lorry attack on a Swedish department store, Sweden's national public broadcaster SVT has reported.
Police are said to believe he is connected to the other man who was arrested earlier.
SVT, citing police sources, said the man was arrested in the northern suburb Hjulsta.
The lorry crashed into shopping centre in Stockholm, killing at least four people, in what the Swedish prime minister has called a terror attack.
The whole of Sweden is "united in grief and anger" following the lorry attack which left four people dead and 15 injured, the country's Prime Minister has said.
"These kinds of actions will never succeed," said Stefan Lofevn.
"We know that our enemies are these atrocious murderers and not each other.
"Our message will always be clear: you will not defeat us, you will not govern our lives, you will never ever win."
Mr Lofven added that the country is "determined to never let the values we cherish be undermined by hatred" and called the crash an "act of terror".
The seconds before a lorry crashes into a department store in Stockholm have been captured on CCTV, showing people fleeing along Drottninggatan, a street in a busy shopping district, and into a shop.
Four people died after the lorry crashed into upmarket department store Ahlens, and 15 others were wounded, nine seriously.
Four people have now died, and 15 others are injured in the Stockholm lorry attack, emergency services said.
Swedish emergency services told the Press Association that nine of those injured had serious injuries.
Swedish police have confirmed that a man "whom we are particularly interested in" has been arrested after a lorry crash which left four people dead.
Jan Evensson of Stockholm police said the arrest was made in Marsta, a suburb in the north of the city which is close to the city's international airport.
Mr Evensson added that the man arrested was "in the vicinity" of the truck crash in Drottninggatan, a street in a busy shopping area.
He continued that the man was spotted by a police patrol and was the man pictured in an image released by the authorities earlier on Friday.
Mr Evensson also urged people not to go into central Stockholm on Friday night.
Stefan Hector of Sweden's national police added the crash was being treated as an "act of terror."
Detectives declined to comment on Swedish media reports that the arrested person was a 39-year-old man from Uzbekistan.
It comes amid confusion over the number of arrests after the attack.
Sweden's national public broadcaster initially reported that a second man was being held.
This was later denied by prosecutor Hans Ihrman and police spokesman Lars Bystrom who said only one person had been arrested in the case.