Belgium said it faced a serious and imminent threat of a Paris-style attack, and kept Brussels on maximum alert on Monday as security forces searched for militants thought to be at large in the capital.
Prime Minister Charles Michel, speaking after a meeting of security chiefs called to review the threat status, said the capital’s metro, universities and schools would be closed on Monday.
For the rest of the country, a threat level of three on a four-tier scale would remain in place, Michel said. Brussels would remain at level four, meaning an attack was imminent, as it has been since Saturday.
“What we fear is an attack similar to the one in Paris, with several individuals who could possibly launch several attacks at the same time in multiple locations,” Michel told a news conference.
Possible targets were malls, shopping streets and public transport, Michel said, adding the government would boost police and army presence in the capital beyond already high levels.
He said a new evaluation of the situation would be made on Monday afternoon and everything was being done to return the city to normal as quickly as possible.
Commuters trying to get to work on Monday are expected to suffer delays as a result of the metro closure, though some companies had already indicated on Sunday they were ready for staff to work from home.
Belgium has been at the heart of investigations into the Paris attacks on Nov. 13 that left 130 people dead after links with Brussels emerged.
In France, investigators on Sunday extended into a fifth day the detention of a man arrested on Wednesday outside the building where the suspected ringleader of the Paris attacks died in a raid. Police also released a picture of a man they said had blown himself up in the attacks and called for witnesses.
Two of the Paris suicide bombers, Brahim Abdeslam and Bilal Hadfi, had been living in Belgium. Fugitive suspected militant Salah Abdeslam, Brahim’s 26-year-old brother, slipped back home to Brussels from Paris shortly after the attacks.
Earlier, Interior Minister Jan Jambon said Salah Abdeslam was not the only security threat.
“It is a threat that goes beyond just that one person,” he told broadcaster VRT. “We’re looking at more things, that’s why we’ve put in place such a concentration of resources.”
Bernard Clerfayt, the mayor of the Brussels district of Schaerbeek, was quoted by broadcaster RTBF as saying there were “two terrorists” in the Brussels area ready to carry out violence.