Catalyzes the halogenation of organic substrates in the presence of hydrogen peroxide. RH + Br(-) + H2O2 = RBr + 2 H2O. Binds 1 Ca(2+) ion per subunit. The binding is important for enzyme stability. Binds 1 vanadate ion per subunit. Optimum pH is 6.0. Homododecamer. Belongs to the vanadium-dependent haloperoxidase family.