Multiple explosions rocked Tripoli on Saturday night and repeated anti-aircraft fire was seen streaking across the sky, a Reuters news agency reporter in the city said as witnesses reported fighting in some neighbourhoods of the Libyan capital.

Crowds of opponents of Libyan leader Muammar Gaddafi were in the streets and gunfire could be heard from multiple locations, two residents told Reuters.

Sustained gunfire and thuds were heard in the distance and residents of Tajoura, on Tripoli's eastern outskirts, reported clashes were under way.

Tripoli residents said fighting had also broken out in the eastern neighbourhoods of Soug Jomaa and Arada.

Gunfire erupted in central Tripoli after the break of the dawn-to-dusk fast of Ramadan.

Tripoli residents also received mobile phone text messages urging them to "go out into the streets to eliminate agents with weapons".

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