The 25 defendants are all young people from Genoa

At a preliminary hearing on Wednesday, a judge said they should go on trial charged with resisting arrest, looting and carrying explosive materials.

Tens of thousands of anti-globalisation protesters gathered in Genoa for the three-day summit in the Italian city.

One protester died and many others were hurt during clashes with police.

The policeman who shot 23-year-old demonstrator Carlo Giuliani was investigated by prosecutors but the case was thrown out by a judge who ruled that he was acting in self defence.

An internal inquiry into police actions during the summit resulted in disciplinary action against the head of Italy's anti-terrorism unit, the country's second highest-ranking police officer and the Genoa police chief.

French news agency AFP said Judge Roberto Fucigna, who ordered the 25 to stand trial, deplored what he called the shortcomings in the judicial investigation.

He said he felt the investigation was only directed at the demonstrators and not the police.

The 25 charged in connection with the riots are all young people from the Genoa region who are said to have links to anarchist groups.