Two Swedish nationals were shot dead in Brussels late Monday by a suspect who remains at large, in an attack the Belgian prime minister described as "terrorism".
The gunman fled on a scooter and Belgium's security observatory raised its terror alert to level four or "very serious" -- the highest -- for Brussels, and level three nationally.
Belgium's premier, Alexander De Croo, said the shooting had targeted Swedes -- the attack came just before a Belgium-Sweden soccer match -- and European leaders were quick to offer their solidarity. Sweden expressed its devastation.
In a video posted on social media, a man identifying himself as the attacker said "he was inspired by the Islamic State" (IS) extremist group, the spokesman for the federal prosecutor's office, Eric Van Duyse, said on the LN24 news channel.
Several Belgian media named the suspect as Abdesalem L, aged 45 of Tunisian origin who lived in Brussels.
De Croo said he had "offered my sincere condolences to the Swedish PM following tonight's harrowing attack on Swedish citizens in Brussels" in a social media post.
"Our thoughts are with the families and friends who lost their loved ones. As close partners the fight against terrorism is a joint one."
Several Belgian media outlets said the two individuals killed were wearing football shirts belonging to the Swedish national team ahead of the game between Sweden and Belgium.
The Group F European qualifier match between the two countries was suspended at half-time "due to incidents," the Belgian side posted on social media accounts.
Around 35,000 fans attended the match and police began to evacuate the stadium.
Officers provided extra protection for Swedish nationals at the game, escorting Sweden's national players directly to the airport to leave safely, Belgium's football association CEO told the country's RTBF channel.
The UEFA website said the match had been halted at half-time at one goal apiece.
A third individual had been hurt in the attack but officials said the person was not in a critical condition.
- 'Stood there frozen' -
A video of a man speaking Arabic and claiming responsibility for the shooting has been circulating on social media.
The federal prosecutor in charge of terrorism cases launched an investigation. Police are only investigating one suspect at the moment based on preliminary information.
The individual claiming the attack said the Swedish nationality of his victims was a motivation, Van Duyse said but added there appeared to be no links with the conflict between Israel and Hamas in the Middle East.
Sweden has been at the centre of a bitter row this year with Muslim countries after multiple burnings of the Koran, Islam's holy book.
"Devastated by the news of two Swedish football supporters murdered in Brussels tonight and a third person being seriously wounded. All my thoughts are with their families and loved ones," Swedish Foreign Minister Tobias Billstrom said.
"Swedish authorities work closely with their Belgian partners to find the murderer," he added on social media.
The shooting took place in the city centre's northern districts. Police had been alerted to the incident after 7:00 pm local time (1700 GMT).
In a video shared online by Flemish newspaper Het Laatste Nieuws, the shooter is seen with an automatic weapon on his shoulder, fleeing on a scooter.
Four gunshots can be heard in the video.
A witness who spoke to LN24 channel described his shock during the incident.
"I stood there frozen, I didn't move. I was shocked by what happened, even now I am still in shock. It was a man who came, pushed me, told me to stop running if I wanted to stay alive," said the witness, who gave his name as Sulayman.
The Belgian royal palace said it was "shocked" by the shooting.
- 'Despicable' -
The president of the European Commission, which is based in Brussels, was quick to condemn the attack.
"Tonight, my thoughts are with the families of the two victims of the despicable attack in Brussels," Ursula von der Leyen posted on social media.
"I extend my heartfelt support to the Belgian police, so they swiftly apprehend the suspect. Together, we stand united against terror."
French President Emmanuel Macron said Europe was "shaken" by an "Islamist" attack in Brussels, while France's interior minister had earlier given instructions to strengthen border controls with Belgium.
Belgium had already been the target of an attack claimed by IS extremists in March 2016, at Brussels' main airport and on the metro system, which killed 32 people.
Sweden facing unprecedented security threat, says PM
Sweden has never in modern times faced a bigger security threat, Prime Minister Ulf Kristersson said Tuesday, calling a shooting in Brussels that killed two Swedes a "terror attack" against his country.
Brussels police on Tuesday shot and fatally wounded the suspected attacker.
"Sweden has in modern times never been under as big a threat as now," Kristersson told reporters after two Swedish football fans were killed and a third injured in the shooting on Monday evening.
"Every indication is that this is a terror attack, targeting Sweden and Swedish citizens, just because they are Swedes," he said, adding he felt an "unfathomable sadness".
In August, Sweden's intelligence service Sapo raised its threat level to four on a scale of five after a series of Koran burnings across the country had made it a "prioritised target".
"It was risks like this that were the reason Sapo this summer raised the threat level from three to four," Kristersson said.
"Now we know with chilling clarity that there was cause for the concern that they and we in the government described," he added.
The prime minister vowed "to protect our open, democratic society".
"They want to scare us into silence ... That's not going to happen," he said.