Hundreds of people had been marching in the capital as part of a historic wave of protests that has swept Lebanon since October 17, furious at a ruling elite that steered the country towards its worst economic crisis in decades.

Since the protests pushed Saad al-Hariri to resign as prime minister in October, talks between the main parties have been deadlocked over forming a new cabinet.

Lebanon urgently needs a new government to pull it out of the crisis.

Foreign donors say they will only help after the country gets a cabinet that can enact reforms.

Riot police and security forces deployed en-masse in Beirut on Saturday night, chasing demonstrators, beating and detaining some of them, a Reuters witness and a protester said.

The forces fired tear gas canisters and rubber bullets, as the two sides raced around streets of central Beirut in cat-and-mouse clashes late into the night.

Protesters pelted stones at police and others tried to push through steel barriers blocking paths to the parliament and government headquarters.

The Lebanese Civil Defence said calm returned to central Beirut by midnight.

The rescue service said it treated 54 people who were wounded, taking more than half to hospital.

The unrest erupted across Lebanon from a build-up of anger at the rising cost of living, new tax plans and the record of sectarian leaders dominating the country since its 1975-90 civil war.

Protesters accuse the political class of milking the state for their own benefit through networks of patronage.

Lebanon's economic crisis, long in the making, has now come to a head with pressure piling up on the pegged Lebanese pound.

A hard currency crunch has left many importers unable to bring in goods, forcing up prices.

Banks have restricted dollar withdrawals and blocked nearly all transfers abroad.

Australian Associated Press