Belgium said on Saturday it will deploy up to 300 soldiers to help guard vulnerable sites in its two largest cities, as governments across Europe stepped up security in the wake of the terrorist attacks in and around Paris last week.

The troops will be deployed progressively from Saturday, and will concentrate on the capital, Brussels, and the port city of Antwerp, Prime Minister Charles Michel said, following a meeting with his cabinet that lasted into the early morning hours Saturday.

It is the first time since the mid-1980s—when left-wing terror groups detonated a series of bombs in Belgium—that the government is using its military to help guard civilian sites in its cities, said defense ministry spokesman Tony Langone.

VIDEO: Terror operation broken up in Belgium

The troops will help guard “strategic and vulnerable places,” including foreign embassies and institutions of the Jewish community, that face a higher threat level, Defense Minister Steven Vandeput told Flemish broadcaster VRT.

Antwerp has a big orthodox Jewish community, while Brussels host embassies not only to Belgium, but also to the European Union and the North Atlantic Treaty Organization.

Michel said some troops could also be deployed outside Brussels and Antwerp, including the eastern city of Verviers, where police killed two men and arrested several others in an antiterrorism raid Thursday. Belgian authorities have said that the suspects had been on the verge of launching attacks on police.

Also Saturday, prosecutors in Brussels interrogated three people who had been detained for allegedly making threats against police. Judges will decide on Sunday whether the three will be formally arrested.

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