A British man killed in the Stockholm lorry attack has been named as 41-year-old Chris Bevington.
Two Swedes and one Belgian also died in the attack on Friday, when a hijacked lorry was driven into a store.
His family said they were devastated by the "untimely and tragic death" of the "wonderful husband, son, father, brother and close friend to many".
The suspect, a 39-year-old man from Uzbekistan, had been facing deportation, Swedish police said.
Crispin Bevington - known as Chris - worked as a director with music streaming service Spotify. The father-of-two was based in Stockholm with his family.
His father John said: "We are all devastated by the untimely and tragic death of our talented, compassionate and caring son Chris.
"A wonderful husband, son, father, brother and close friend to many.
"The family requests absolute privacy at this incredibly difficult time to mourn his passing in peace."
Co-founder of Spotify, Daniel Ek, confirmed Mr Bevington's death with "shock and a heavy heart".
He said: "He has had a great impact on not just the business but on everyone who had the privilege to know and work with him.
"There are no words for how missed he will be or for how sad we all are to have lost him like this.
"Whilst this terrible news is sinking in, our primary focus is on supporting the family and loved ones of Chris in any way we possibly can.
Mr Ek said he was as "deeply saddened and upset" as everyone that such an attack could happen in Sweden. The only light, he said, was the consequent "outpouring of love, compassion and solidarity".
He added: "We will greatly miss you Chris. Rest in Peace my friend."
In a press conference on Sunday, police said the suspect was known to have extremist sympathies.
A further 15 people were injured in the attack. Ten are still being treated in hospital, four of them in a serious condition.
Police later said they had found a suspect device inside the lorry, which had been hijacked from a beer company before hitting the Ahlens store.
No terrorist group has claimed to be behind the attack.
A UK Foreign Office spokesman said: "Stockholm Police have confirmed that a British man was killed during the attack in Stockholm.
"We are supporting his family in Sweden and in the UK. Our thoughts are with them and all those affected at this terrible time.
"We will stand shoulder to shoulder with Sweden as they deal with this tragedy."
Stockholm police said the suspected attacker, arrested later on Friday, had previously been sought by authorities for deportation.
He had sought residency in Sweden in 2014, but his application was rejected last year. He had expressed support for extremist organisations including the Islamic State group, police said.
While he was known to security services, he was seen only as a "marginal character", Sweden's National Police Commissioner Dan Eliasson added.
Meanwhile, a second suspect has been placed under formal arrest.
Reuters news agency said it was on "a lower degree of suspicion" than the first suspect.
Police have interviewed more than 500 people over the incident, Sweden's TT news agency reports.
Thousands of people have gathered in a square in central Stockholm on Sunday for a vigil against terrorism.
Prime Minister Theresa May pledged solidarity with Sweden in the wake of the attack, with a Downing Street spokesman saying she had called her counterpart, Stefan Lofven, to express her condolences.
The spokesman added: "She was clear that the UK stands firmly by Sweden's side, and they agreed on the importance of working together to tackle these threats, which we all continue to face."
Sweden has taken in nearly 200,000 refugees and migrants in recent years - more per capita than any other European country.
However, there was a drop in numbers last year after the country introduced new border checks.
Separately, more than 300 people have gone to fight in Syria and Iraq, making Sweden per capita one of the biggest exporters of jihadists in Europe.