Sixteen people were arrested in Belgium after a series of raids Sunday across Brussels, although a fugitive wanted in connection with the Paris attacks wasn't among them, Belgian federal prosecutors said.
The raids came as heavily armed troops and police deployed across Brussels and as the city prepared to remain under maximum threat level for a third day Monday after warnings of a Paris-style attack. The country's prime minister, Charles Michel, described the threats as "serious and imminent."
"I indicated yesterday that what we are concerned about an attack similar to the one that was carried out in Paris involving several individuals and maybe targeting attacks on several sites simultaneously," Michel said.
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Schools were to remain closed Monday, and public events and transportation were to be canceled.
At a briefing Sunday night, prosecutors — citing an ongoing investigation — took no questions from reporters and provided few details of the 16 arrests, although they said that no firearms or explosives were recovered during the raids and that the fugitive, Saleh Abdeslam, 26 was not among the people taken into custody.
Earlier Sunday, Abdeslam's brother, Mohamed Abdeslam, pleaded with him on Belgian television to turn himself in. Saying Salah Abdeslam "does not represent" his family, Mohamed Abdeslam told the broadcaster RTBF that he "would rather see Salah in prison than in a cemetery."
Prosecutors said that multiple houses were searched in Brussels, Liège and Charleroi and that at one point, a vehicle in the Brussels area of Molenbeek "came toward the police." Authorities fired twice and the car was later intercepted in Brussels, where an "injured individual" was arrested, said one of the prosecutors, Eric Van der Sypt, adding that it was "impossible to say if there's a link between the arrests and the investigation."
Prosecutors also thanked social media users for not identifying operation locations after Belgium's defense minister, Steven Vandenput, posted this message on Twitter earlier in the day: "Police are asking the public not to report their movements on social media, please support & rt #BrusselsLockdown"
Investigators are still untangling the connection between Brussels and the Paris attacks. The terrorists were French and Belgian, and the man suspected of organizing the attacks, Abdelhamid Abaaoud, 27, grew up in Molenbeek. He was killed during a raid Wednesday in Saint-Denis.