Clashes at Italian anti-US demonstration

Protesters have pelted riot police with rocks during an American Independence Day demonstration against the $US500 million ($A632.27 million) enlargement of a US military base in Italy.

An AFP photographer says youths among hundreds leading a march on the base on Saturday hurled bottles at police who responded with tear gas on the approach to the construction site at a former airport in northern Vicenza.

The work at the base - which has a current troop capacity of 2,750 - will enable 1,800 soldiers presently based in Germany to be stationed there.

Pic: Demonstration Vicenza 090704

Demonstrators who have regularly cut their way through barbed wire guarding the site shouted "No arms here" and "We won't be a rear base for the killing of Afghan kids".

Local authorities have backed the extension, with around 1,200 jobs created, while successive governments led by centre-left Romano Prodi and current Prime Minister Silvio Berlusconi have each greenlighted the work.

A delegation from the organisers - a coalition of Communists, Greens and far-left groups - will travel to central L'Aquila on Sunday to protest against the scene of next week's G8 summit of world leaders including US President Barack Obama.