Stockholm  - Swedish police have released all but 20 of 114 right-wing extremists detained for giving Nazi salutes on the country's national holiday, officials said Saturday.

A spokesman said those held for actions "calculated to incite racial hatred" included several minors and teenagers.

Clashes broke out between right-wing and left-wing demonstrators in Gothenburg and in Stockholm, where an estimated 1,000 to 1,500 neo-Nazis took part in a rally.

Sweden's national day honours the accession to the throne of King Gustav Vasa on June 6, 1523, which marked the foundation of the country as an independent state. It has only been an official public holiday since 2005. (dpa)