The shooting caused Belgium's Euro 2024 qualifier against Sweden to be abandoned at half-time on Monday night.

Fans were also kept in the stadium as armed officers searched for the suspected attacker - who has not yet been found.

The shooting took place about three miles (5km) from the 50,000-seater King Baudouin Stadium shortly after 7pm local time - around 45 minutes before kick-off.

Shortly after, a man who claimed to be the gunman appeared on social media in a video in which he claimed to be a member of Islamic State (IS) and a "fighter for Allah".

He also claimed he had carried out the attack in "revenge in the name of Muslims".

One Belgium newspaper said a witness heard the gunman shout "Allahu Akbar" - "God is great" in Arabic - before the shots were fired.

Another video, reported to be of the incident, which has not been verified by Sky News, showed a gunman in a fluorescent orange jacket and a white helmet chasing a man into a building before shooting at him.

Belgium's interior minister, Annelies Verlinden, said the suspect was "actively being tracked down".

Belgium's National Crisis Centre raised the terror alert in the city to the highest level on Monday night. It was also moved to the second highest for the rest of Belgium.

A spokesperson for Belgium's federal prosecutor's office told reporters that the investigation was focusing on "a possible terrorist motivation for the shooting".

Eric Van Duyse said: "During the evening, a claim of responsibility was posted on social media, having been recorded by a person claiming to be the assailant. This person claims to be inspired by Islamic State."

He said the Swedish nationality of the victims had been put forward as the probable motive for the attack - but said there was nothing to suggest a possible link with the current situation between Israel and Gaza.

A police spokesperson confirmed that two people had been killed in a shooting, but declined to give further details.

The country's prime minister, Alexander de Croo, meanwhile, appeared to link the incident to terrorism.

In a post on X, formerly known as Twitter, he wrote: "I have just offered my sincere condolences to the Swedish prime minister following tonight's harrowing attack on Swedish citizens in Brussels.

"Our thoughts are with the families and friends who lost their loved ones. As close partners, the fight against terrorism is a joint one."

In an earlier post, he offered his "deepest condolences" to the relatives of those killed in what he described as a "cowardly attack".

He also urged the residents of Brussels to "be vigilant".

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Swedish justice minister, Gunnar Strommer, said his government was working with authorities in Belgium "to get more information about what happened".

Prime Minister, Ulf Kristersson, urged Swedes in Belgium to stay vigilant and follow the instructions of the local authorities.

Meanwhile, France's President Emmanuel Macron described the incident as an "Islamist terrorist attack".

Speaking in Albania on Monday evening - days after his own country was rocked by the fatal stabbing of a teacher in a suspected terror attack - Mr Macron said: "Europe is being shaken".

The shooting in Brussels took place near Boulevard d'Ypres - in an area to the north of the city centre.

The area is around three miles (5km) from the King Baudouin Stadium, where the Euro 2024 qualifier was held.

A UEFA spokesperson confirmed the game had been suspended on Monday.

In a statement, UEFA said: "Following a suspected terrorist attack in Brussels this evening, it has been decided, after consultation with the two teams and the local police authorities, that the qualifying match between Belgium and Sweden is abandoned."

Sweden coach Janne Andersson later told Swedish website Fotbollskanalen: "We can't play football in this situation. We and Belgium completely agree that we shouldn't play."

Laura Demullier, of Belgium's OCAD anti-terror centre, said getting the thousands of football fans attending the match safely out of the stadium was their top priority.

Over two hours after the game was suspended, a message flashed on the big stadium screen which said: "Fans, you can leave the stadium calmly."

Sweden has in recent months faced rioting following a string of Koran-burning incidents in both Sweden and neighbouring Denmark.

Muslim leaders in Sweden have called on the government to find ways to stop the Koran burnings, but police have allowed them, citing freedom of speech.