Officials said clashes between left-wing protestors and police got ugly, with protestors throwing stones and fireworks at police who were trying to stop them from running through the town centre.
Around 700 neo-Nazis had gathered for a rally in the city, which had been approved by the authorities although a planned march had been banned. Police were ordered to protect their rally which was held in a car park.
The roughly 3,000-strong counter-demonstration, marching under the banner “Dortmund stands in the way,” was initially peaceful, but groups broke off from the main gathering and tried to make their way into the town centre, battling police as they went.
Ten police officers were injured while a local Green politician was slightly hurt while trying to stop people throwing stones at police car. A woman was also reportedly injured, although there were no further details about her.
The police also said that 15 of their vehicles were damaged. They arrested around 300 people.