According to de Maiziere, it is yet unclear whether the series of blasts in the Belgian capital is over.
“So far, it seems clear that the terrorists attacks hit an international airport and a metro station close to the EU institutions. This suggests that the attack was directed not only against Belgium, but also against our liberty and freedom of movement. And against everyone who is part of the EU," de Maiziere told reporters.
Brussels hosts sessions of the European Council, the European Parliament and several other EU institutions, as well as being home to the NATO headquarters.
According to media reports, the Islamic State jihadist group, outlawed in many countries including Russia and the United States, has claimed responsibility for Tuesday's attacks in Brussels.