BRUSSELS is said to be like a scene from "one of those zombie apocalypse films" as the Belgian city goes into a second day of lockdown.
Schools will be closed on Monday, while the Metro underground system will also remain closed to the public, as the government warns of a "serious and imminent" threat of coordinated, multiple attacks.
It will be the second day running that Brussels will sit at its highest threat level, while the rest of the European nation will stay at a level three, on a four-tier scale, Reuters reported Belgium's prime minister, Charles Michel, as saying.
"What we fear is an attack similar to the one in Paris, with several individuals who could also possibly launch several attacks at the same time in multiple locations," Michel told a press conference in Brussels.
The lockdown means many public events have been cancelled and public buildings closed.
UK newspaper The Independent's Brussels correspondent, Leo Cendrowicz, told Newstalk ZB the Metro underground was "completely closed", as well as many of the top department stores, and events like football matches, concerts, and cinemas, had been cancelled.
"Since it's Sunday a lot of this wouldn't matter too much, apart from the fact that you have famous markets here in Brussels, including the one at Place du Jeu de Balle, which features in one of the Tin Tin books and was featured in the film that Peter Jackson made a few years ago. These are famous these markets, and they're all closed," he told Newstalk ZB this morning.
"The big question now is what happens next."
The security alert has been elevated after fears one of the Paris attackers is in Brussels and may be planning a similar series of coordinated attacks.
Salah Abdeslam, 26, was driven back to Brussels in the early hours of the Saturday morning following the terror attacks in Paris on November 13.
His older brother, Brahim Abdeslam, 31, detonated a suicide vest outside the Comptoir Voltaire cafe, close to the Bataclan theatre where 89 people were killed.
"We know that Abdeslam was actually driven back to Brussels in the early hours of that Saturday morning after the attacks, and the two people who drove him are in police custody," Cendrowicz said.
"The lawyer of one of those people has said on TV that he was in the car and he seemed nervous, and while he didn't have any weapons on him, he had a bulky jacket which could have been concealing a suicide belt. So there's a question there about whether he's planning something dramatic.
"There are also reports that he was actually very disappointed that he couldn't blow himself up in Paris, he was very cross with himself, there might have been something which went wrong with his bomb.
"Whatever the case, there is the risk that he's here in Brussels and he's planning to do something and that's why the police are out in force and that's why they're cancelling all sorts of events."
People in Brussels were "very nervous", Cendrowicz said.
"A lot of people are staying inside, there's lots of rumours going around, there are false alerts, and it's a bit of a strange situation," he said.
"A lot of the streets are quite quiet, there are some areas where there's still activity but, some areas. it's completely deserted. It feels like one of these zombie apocalypse films, it's really eerie and strange."
The police and army presence in the city has been boosted during the lockdown, Reuters reported.
Belgium has been at the heart of investigations into the Paris attacks after links to Brussels, and the poor district of Molenbeek in particular, emerged, Reuters reported.
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