LEIPZIG, GERMANY -- German police said demonstrators protesting coronavirus restrictions attacked them in the city of Leipzig Saturday, after the crowd was told to disperse.

"There were numerous attacks against security forces," police tweeted while media broadcast images of projectiles and fireworks thrown at police who had established a security cordon near the city's main train station.

The crowd in the eastern German town was estimated to number around 20,000 and German media reported that some of those who clashed with police were members of far-right groups.

Organizers of the protest called for "the immediate lifting of restrictions to fundamental rights" arising from measures taken to prevent the spread of Covid-19.

Police ordered the demonstrators several times to respect a distance of 1.5 metres (yards) from each other and to wear protective masks.

According to the regional public television MDR, flags recalling the German empire that collapsed after World War I were waved by some protesters, and members of the neo-Nazi group NPD were reportedly seen in the crowd.

Saxony, the state where Leipzig is located, is considered a stronghold of far-right German nationalists, but the rally organisers consider themselves "free-thinkers" representing a range of political and social movements.

The demonstrators are closely tracked by German authorities, especially since several hundred protesters forced their way past police barriers and onto the steps of the national parliament in late August.