A Belgian minister has warned of more Euro 2016 terror plots as it emerged a dozen suspects remain in custody following a series of raids.

In a mass operation, police arrested 40 people in Brussels, Liege and Anderlecht in the early hours of Saturday morning.

Amid fears of an 'imminent' attack on Euro 2016 football fanzone, Interio Minister Jan Jambon warned: 'It's not over'.

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Belgian soldiers walk the streets of Brussels today after a suspected terrorist cell was dismantled overnight. Suspects were seen scoping out a fanzone where today fans will watch Belgium's game against Ireland

Police officers search a man's backpack in central Antwerp. The whole of Belgium is in a state of high tension

He added: 'All of those arrested in the raid were initially held, and twelve remain in detention.'

Referring to a threat scale which goes from one to four, Mr Jambon added today: 'We remain under terror alert three, which means something is still up.'

Heavily armed special forces police officers wearing balaclavas carried out the raids on well over 100 flats, homes and garages.

Belgian police said the raids 'passed off without incident' and said 'no arms or explosives were found'.

They searched 152 garages and lock-ups in Brussels, Molenbeek, Schaerbeek, Anderlecht, Koekelberg, Sint-Agatha-Berchem, Evere, Frost, Boitsfort, Ganshoren, Zaventem, Ninove, Wemmel, Fleurus, Tubize and Liège.

A bomb squad unit was also called to the train station in the city of Antwerp after a suspect package was reported.

While no arms or explosives were found, Mr Jambon hailed the operation as a 'great success'.

Tonight, Federal prosecutors said three men arrested in the raids had been charged with 'attempting to commit a terrorist murder, and participation in the activities of a terrorist group'.

Belgian soldiers, their faces covered, stand guard outside the prime minister's office today

Belgian's prime minister Charles Michel (pictured) urged people to remain calm but vigilant

They were identified as Samir C., 27, Mustafa B., 40, and Jawad B., 29, and came from the 'Brussels area', said a prosecuting source. All now face trial, and possibility of a life sentence in prison.

The source added: 'Phone taps enabled investigators to work out what the group was up to. When enough evidence was gathered, the raid was launched.'

All those charged were allegedly in the 'inner circle' of the El-Bakraoui brothers, who blew themselves up during the airport and Metro bombings in March.

Another of the suspects arrested over Friday night - who has not yet been charged - was said to be working at Zaventem Airport in Brussels.

Identified as Youssef E.A, 29, he was also a childhood friend of Khalid El Bakraoui, one of the suicide bombers in Brussels' Maelbeek metro station on March 22nd.

The man had direct access to flight information, and police are said to have found messages on his computer allegedly sent to El Bakraoui which stated that planes from America, Russia and Israel take off every Tuesday from Zaventem.

Belgian police officers patrol in central Brussels today, following overnight raids on terror suspects

A French RAID commando keeps tabs on the stadium in Bordeaux. RAID commandos were involved earlier in the week when they shot dead a man claiming allegiance to ISIS after he killed a Paris police commander and his wife at their home

In the wake of the charges, Belgian Prime Minister Charles Michel announced that Euro 2016 fanzones would remain in place, but with extra security measures.

'We want to continue living normally. The situation is under control,' said Mr Michel.

'We are extremely vigilant, we are monitoring the situation hour-by-hour and we will continue with determination the fight against extremism, radicalisation and terrorism.'

ISIS terrorists struck in Belgium in March, in two coordinated attacks that led to 32 people being killed by suicide bombers at the city airport, and an underground station.

They were part of the same ISIS cell that attacked Paris in November 2015, killing almost 150 people in one night of extreme violence.

A football international at the Stade de France between France and Germany was among the targets for bombers, and Isis has since said that Euro 2016 is a prime target.

Mr Jambon said a car containing suspected terrorists had been spotted close to a Brussels fanzone on Friday.

Belgians walk past a bomb squad van outside the central station in Antwerp. Police and the bomb squad unit responded to a suspect package in the station as the country was put on heightened alert

Police carry out checks inside the stadium in Bordeaux prior to today's game

This was the day before Belgium played Ireland in a Euro 2016 tie attracting an audience of hundreds of thousands, including many watching in the Brussels fanzone.

The Belgian team, known as the Red Devils, played in Bordeaux this afternoon but it is thought Brussels was the target.

In the event the game passed off without incident, Belgium winning 3-0.

Charles Michel, the Belgium prime minister, said his country would 'remain extremely vigilant, hour by hour', because the threat of an attack was 'possible and likely'.

Following a security council meeting, Mr Michel said: 'We'll take additional and adapted measures in the coming hour.'

Mr Michel and Mr Jambon are among four senior measures who are receiving special protection following specific threats, said the Prime Minister.

The game between Belgium and Ireland (pictured, with Belgium in the red kit) has now kicked off in Bordeaux and security is high in the Belgian capital, especially around the fanzone

Belgium's Romelu Lukaku celebrates the first of his two goals against Ireland

On Wednesday, Belgian police received an anti-terrorism alert warning that a group of Isis combatants had recently left Syrian, and were en route to the EU.

Many of the Belgium and French nationals who carried out the attacks on Paris and Brussels had spent time training with Isis in Syria.

Security experts in both France and Belgium have warned that Euro 2016 fanzones in major cities such as Brussels and Paris could easily turn into deathtraps if they are targeted by the kind of Kalashnikov-weilding suicide bombers involved in earlier attacks.