Around 15,000 people
had set off late on Tuesday afternoon from Kreuzberg, a neighborhood of Berlin, heading for the city centre, but the demonstration was halted as left wing demonstrators clashed with the police.
threw bottles, stones and firecrackers at the riot police. The police responded with batons and pepper spray. Arrests were made and over 100 people were detained overnight
In Hamburg, Germany a similar demonstration, themed "No Alternative to Revolution" saw 1 000 leftist activists gathered for the annual May Day protest march. Protesters marched from St Pauli to Ottensen. However, right at the beginning of the march, protesters threw fireworks at police officers, while most of the crowd remained calm for the rest of the march.
However, following a speech marking the end of the demonstration, violence erupted, with bottles and stones thrown at the policemen who were escorting the march.
Police in Hamburg responded with pepper spray and arrested several protesters. There were injuries reported on both sides.
In Hamburg's Schanzenviertel neighborhood, notorious for past May Day violence, riots broke out later in the day.
Huffington Post has photos
of the protests.