German police say they were well-prepared for a far-right protest that erupted into violence in the western city of Cologne, resulting in 49 officers being injured Sunday.

Wolfgang Albers, the city's chief of police, defended his officers' tactics Monday after conservative lawmakers accused police of underestimating the situation.

Some 4,000 neo-Nazis attended the demonstration, organized by a group calling itself "Hooligans against Salafis" and ostensibly aimed against Islamic extremism.

Police commander Klaus Rueschenschmidt said the violence started when protesters felt "provoked" by a person wearing the team jersey of Turkish club Galatasaray.

Protesters subsequently threw bottles, stones and fireworks at police, attacked journalists and bystanders, and overturned a police vehicle.

Seventeen people were detained in the unrest.