NAPLES, Italy Thousands of anti-globalization protesters clashed with riot police in the center of Naples on Saturday, throwing rocks and smoke bombs in a demonstration against a conference being held in the city.

Witnesses said at least seven police were injured by flying rocks and were treated for bleeding head wounds. Four journalists were also injured and their television cameras damaged, a Reuters photographer at the scene said.

Police fired teargas to try to disperse the crowd and helicopters circled overhead monitoring the situation. After around 20 minutes of fighting the situation was brought under control, police said, but forces remain on high alert.

"There are still areas of tension, we will have to be extremely vigilant for the next few hours," Naples police spokesman Nicola Izzo said.

He said there had been several injuries among the police and demonstrators and a number of people had been arrested. Witnesses said police made around 100 arrests.

Organizers said 25-30,000 people gathered at the main train station before marching through the streets of Naples and then clashing with police as they tried to gain access to a meeting of the global forum, a conference of government and technology leaders."

Police said the number of demonstrators was closer to 10-15,000.

The demonstrators arrived in the southern port city early on Saturday on trains from Milan and Palermo. As well as anti-globalization groups from across Italy and the rest of Europe, the crowd included thousands of unemployed.

Around 4,000 riot police were drafted into the city on Wednesday and Thursday, sealing off the center with barricades and riot vehicles in preparation for possible clashes.

(Reuter)