Belgian Soldiers Patrol Antwerp's Jewish Quarter

Belgian paratroopers fanned out Saturday to guard possible terror targets across the country, including some buildings within the Jewish quarter of the port city of Antwerp, amid heightened security threat.  Read more: Belgium sends troops to Jewish sites, Britain boosts patrols amid raised terror fears

It was the first time in 30 years that authorities used troops to reinforce police in Belgium’s cities, and came a day after anti-terror raids netted dozens of suspects across Western Europe.

Belgium has increased its terror warning to 3, the second-highest, following the anti-terror raids of Thursday which left two suspects dead amid fears they had been planning imminent attacks on police and their office.

French, German, Belgian and Irish police had at least 30 suspects behind bars on Friday and in Brussels, authorities said a dozen searches led to the seizure of four Kalashnikov assault rifles, hand guns and explosives. Several police uniforms were also found, which Belgian authorities said suggested the plotters had intended to masquerade as police officers.

The seizures followed an anti-terrorism sweep on Thursday in and around Brussels and the eastern industrial city of Verviers in which two suspects were killed in a firefight and a third wounded. Authorities said the follow-up operation netted several returnees from Islamic holy war in Syria.

Some 150 paratroopers were watching synagogues in Antwerp, the Jewish Museum in Brussels and other selected building across the nations. The figure could be double in the coming days until the situation will be reviewed next week.