The tensions between the two sides increased through the 1980s and 1990s as the house developed into a centre for radical left-wing activities. The users of the house also became a thorn in the eye of the police as the users often were involved in clashes with these during demonstrations, evictions of squatted houses, etc. In 1987, the police mounted a raid on Ungdomshuset equipped with machine guns. The raid led to six arrests but since the police did not find anything illegal in the house they all were released without charges.