BERLIN (AP) — Berlin police confiscated weapons and a large quantity of munitions in a series of raids Wednesday focused on a man they allege is connected to Islamic extremism.

Police said the 40-year-old German citizen was taken into custody in the overnight raids in four locations and was expected to be brought before a judge later in the day.

Authorities say the raids came after an investigation that started in June with the arrest of a drug dealer and that they decided to act over fears that the weapons could be used in an attack, even though no concrete plans were known.

Police spokesman Winfrid Wenzel said investigators found handguns, rifles and 20 to 30 cases of ammunition.

Wenzel said that the suspect had visited mosques that were of “particular interest” to authorities. He told n-tv television that authorities were concerned that he either “might have been pursuing an idea” with the weapons or planned to give them to other people.