'Imminent' Terror Threat Shuts Brussels Metro

1. An army vehicle passes a police van in the centre of the city
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   Police tape bars people from using Porte de Namur station
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   A station information board informs people that the Metro network is closed
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   The normally busy stairways are empty
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   Soldiers guard the Brussels Radisson Blu, the day after another hotel in group was hit by terrorists
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    Police enter a Thalys train that is bound for Paris
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    Heavily armed troops and officers walk through the street of the Belgian capitalBelgium's Prime Minister said the terror alert was as a result of "quite precise information about the risk of an attack like the one that happened in Paris".

Belgium's Prime Minister said the terror alert was as a result of "quite precise information about the risk of an attack like the one that happened in Paris".

Heavily armed soldiers and police are patrolling the city amid fears at least one suspect in the Paris attacks could be in Belgium.

The website of the country's crisis centre said it had asked local authorities to cancel large events, urge people to avoid crowds and postpone soccer matches.

Belgian PM Charles Michel said the government would review the security situation towards the end of the weekend.

It comes after a meeting of top ministers, police and security services in the city, which is also home to the European Union and NATO headquarters.

A spokesman for the crisis centre said in a statement: "Following our latest evaluation... the centre has raised its terror alert to level 4, signifying a very serious threat, for the Brussels region.

"The analysis shows a serious and imminent threat requiring specific security measures as well as detailed recommendations to the population."

Sky's Enda Brady, who has arrived at the main Bruxelles Midi train station, said: "Extraordinary security scenes here. Soldiers from the Belgian army carrying assault rifles... in groups of four up and down the main concourse and on platforms.

"It's a totally surreal atmosphere. It's just extremely quiet. It's normally a very very busy station, especially at weekends. Belgian police also heavily armed. Everyone knows what's going on..."  

Belgium, and Brussels in particular, have been at the centre of investigations into the Paris attacks after it emerged that two of the suicide bombers had been living in the country.

Three people detained in Brussels are facing terrorism charges.

The brother of one of the suicide bombers, who was also living in Brussels, is still on the run.

Salah Abdeslam was briefly pulled over by French police near the Belgian border last Saturday morning along with two of those in custody.

The Federal Prosecutors Office in Brussels said on Saturday that police had searched the house of a person who was arrested on Friday and had found "a few weapons".

The last time any part of the country was put on maximum alert was in May 2014 when a gunman shot dead four people at the Jewish Museum in Brussels.