BRUSSELS—Belgium raised the terror alert in Brussels to the highest level on Saturday, as Prime Minister Charles Michel warned of the risk of attacks in the capital similar to those that rocked Paris eight days earlier.
“The level four was set for Brussels based on a serious and imminent threat,” Mr. Michel said at a news conference following a meeting with cabinet members. “This is the result of relatively precise information of a risk of attacks, similar to those that took place in Paris.”
The move meant the city’s metro system was closed until Sunday, some tram stations stopped operating and soldiers were deployed outside the entrances of many hotels and throughout the capital. It came a week after Paris was struck by a series of attacks that killed 130 people, which French authorities have said were plotted in Brussels.
Mr. Michel said public transport as well as shopping districts were at particular risk. He declined to give further details on continuing investigations and whether any specific terrorist plots had been thwarted.
The U.S. Embassy in Brussels urged Americans to “shelter in place,” stay at home and avoid public transit. The North Atlantic Treaty Organization, whose headquarters are in Brussels, also recommended that staff and their families avoid public transit and public gatherings in Brussels. The city is also home to the European Commission and many European Union institutions.
There were few details about the specific intelligence that led Belgian authorities to issue the terror warning or prompt the U.S. and NATO to issue guidance to their personnel. Officials said releasing more information could jeopardize investigations.