Belgium's terrorism threat level is based on a 1-4 scale, with 1 being the lowest and 4 being a risk of imminent attack. Authorities are maintaining a level 4 standing in Brussels, the country's highest order of alert, while the rest of Belgium is graded as being of a level 3 risk. Officials are expected to reassess these levels Sunday afternoon
Terror threat level maintained at highest alert in Brussels; authorities to reassess Sunday afternoon - @CrisiscenterBE