Dividing his forces, Civilis suddenly made a simultaneous attack on all four Roman garrisons-the Tenth at Arenacum, the Second at Batavodurum, and the auxiliary horse and foot at Grinnes and at Vada.
20. Hainbesteko gerra falta zen, ezen Zivilek kohorteen, hegalen, legioen posizioak egun bakarrean esetsi baitzituen, armada lau zati eginik.