Fishermen protesting against high fuel prices have clashed with police outside European Union headquarters in Brussels.

Riot police armed with shields and batons charged protesters, who retaliated by hurling flares, firecrackers and rocks.

They also fired flare guns at the European Union headquarters building.

As they retreated down the main boulevard through Brussels' European Union district, protesters broke into some EU buildings, smashing windows and dragging out flags and other material to light bonfires in the street.

Before the violence broke out, about 400 fishermen from France, Italy, Spain and Portugal besieged the EU's headquarters for several hours.

Fishermen, truck drivers and farmers across Europe have protested in recent weeks to demand government aid to help compensate for high fuel costs, which they say are threatening their livelihoods.

Europeans are faced with higher fuel prices than elsewhere because of excise taxes that are added to national sales tax.

EU leaders have put the problem on top of their June 19-20 summit agenda.

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