Authorities and businesses in Essen were preparing on Friday ahead of anticipated demonstrations against a weekend party congress of the far-right Alternative for Germany (AfD) being held in the western German city.
Businesses around the congress venue in the Rüttenscheid area to the south of the city centre, boarded up their windows as a police helicopter circled overhead.
Cars were being diverted away from the area, and the popular Grugapark with its open-air swimming pool was closed to visitors. Residents were asked to identify themselves before entering the area on foot only.
Police are anticipating up to 100,000 people to demonstrate against the party during the weekend, with particular concern over an estimated 1,000 left-wing extremists expected to descend on the area.
One gift shop on a popular shopping street put up a sign reading "Forced Closure." An irritated owner said: "If the customers can't get here in any case, I might as well close up shop." Some business boarded up their windows for fear of riots.
A tented encampment for up to 4,000 activists on the banks of the Ruhr River a couple of kilometres outside the city was filling up on Friday.
The "Camp against Racism" had originally been planned for a more central location but was prohibited by police order on security grounds and shifted to the outskirts of the neighbouring city of Bochum.
The AfD is to elect a new executive at the congress being held on Saturday and Sunday. Efforts by the city authorities to prevent the party congress were rejected by the courts.
