The incident followed a similar attack in London last month when a man drove a auto into pedestrians on a bridge, then tried to rush onto the grounds of Parliament before he was shot and killed.
Swedish Prime Minister Stefan Lofven has called it a terrorist attack, with borders tightened at his request.
Hundreds of flower bouquets covered steps leading down to the square next to where the truck ploughed into the Ahlens department store, with more piled up under boarded-up windows.
If the suspect is confirmed as the perpetrator, that would bring to three the number of attacks in less than four months by an assailant believed to have links to Uzbekistan.
Details around the suspected terrorist, a 39-year-old Uzbekistan man, have now been released with Swedish police revealing he was an asylum seeker who had his application rejected in June last year and was wanted for deportation by immigration officials. On Feb. 24, he was formally sought after by Swedish police. The suspect was arrested several hours later.
She said lawyer Johan Akerman was the legal council appointed. Four others were being held by police. "On the contrary, suspicions have strengthened as the investigation has progressed".
It is unclear yet whether more people were involved in the truck attack, but it is not ruled out by police.
Britain's foreign office named United Kingdom citizen Chris Bevington as among the dead, but gave no details on the victim. Press Association said he was 41.
There are no reports about the identities of other victims yet.
Swedish media today identified the main suspect in the Stockholm truck attack as Rakhmat Akilov, an Uzbek construction worker and father-of-four who went underground to avoid being deported from Sweden.
Soderberg said it was important that caregivers continue to give "long-term psychological support to those who need it".
"People were screaming and running in all directions", said Brandon Sekitto, who was in his vehicle nearby.
Last December, 12 people were killed and at least 48 people were wounded when a truck drove into a Christmas Market in Berlin.
Ciuraru, who expects to be released Monday from the hospital, said she "tried to get up and run but got a huge rock over my leg".
People gather in Sergels torg in central Stockholm for a "Lovefest" vigil against terrorism following Friday's attack, April 9, 2017.
Addressing tens of thousands of people rallying in bright sunshine on the downtown Sergelstorg square, organizer Rickard Sjoberg noted that many in the crowd probably were from out of town.
However, the attack left Swedes divided.
"We don't respond with fear, we respond with love", read one poster held by a woman wearing a headscarf.
Flags flew at half-mast at public buildings across Stockholm.
"The only light in this deeply tragic moment is the outpouring of love, compassion and solidarity that we have seen from everyone", said Spotify founder Daniel Ek on Facebook.
"We want to talk to everybody who knows anything about this and sometimes it's better to talk at the police station than place of event". "We want to have, as before, a free life and we welcome people from overseas".
Photos from the scene showed a beer truck sticking out of the department store, and Aftonbladet daily reported that Swedish beer maker Spendrups said one of its trucks had been carjacked earlier Friday.
Live television footage showed smoke coming out of the upscale Ahlens department store on Drottninggatan Street, which the truck smashed into. It was quickly put out.
Answering reporters' questions on Vietnam's response to the attack, Hang said on April 8 that "We extend our deep sympathies to the Swedish Government and people, especially families of the victims".
Police apparently never found the man, whom authorities have said was known to Sweden's intelligence service for undisclosed reasons.