Tens of thousands of people took part in protests in central Paris and Rome on Saturday, April 12, organized by hard-left parties against government economic reform plans and austerity measures, according to Reuters.

The protest in Rome turned violent when a large splinter group - many wearing masks and helmets - threw rocks, eggs, firecrackers and oranges at riot police in front of the industry ministry.

Riot police with batons charged the group, with protesters fighting back with rocks and firecrackers. One man lost a hand when a firecracker exploded before he could throw it.

There were dozens of lighter injuries among police and protesters, and at least six arrests, police said.

In Paris, protestors marched from the Place de la Republique, some carrying banners attacking President Francois Hollande with slogans such as "Hollande, that's enough" and "When you are leftist you support employees."

French police said that about 25,000 joined the protest, which came after new Prime Minister Manuel Valls unveiled planned tax and spending cuts on Tuesday, vowing to bring down France's public deficit and following on the heels of pro-business reforms announced earlier this year by Hollande.

Valls was appointed prime minister in a reshuffle this month after Hollande's Socialist Party suffered a drubbing in recent local elections where the far-right National Front made strong gains. Leftist allies grumble that Valls is too centrist.

Polls show that the ruling Socialist party will finish third in next month's European elections, behind the conservative UMP and the National Front.

Paris is under EU disciplinary action for running too high a budget gap and has already been granted a two-year delay to reduce it to within the EU limit of 3 percent of gross domestic product by the end of 2015.