PARIS • Hundreds of police officers have taken to the streets of Paris for a third night of demonstrations calling for reinforcements and stiffer penalties following a string of attacks on officers.

Protests also took place in other French cities on Thursday night despite the government's efforts to contain growing anger among the police as the issue of safety of law enforcement officers enters the presidential race.

Around 500 officers, most dressed in civilian clothes and some with their faces partly covered, protested near the Eiffel Tower. Under French law, the police may protest only when off duty, out of uniform, and if they leave service weapons and vehicles behind.

"Police officers need recognition," Prime Minister Manuel Valls said earlier on Thursday.

"They are loved by the French people, and not only since Charlie," he said, referring to an outpouring of sympathy for the police following the attack last year on the Charlie Hebdo magazine. The killing of a police officer during the assault by two extremists was the first in a string of Islamist-inspired attacks that have shocked France.

"I call for calm and peace, and I say to the police officers of France that they can count on my support, my solidarity, my understanding and my commitment," Mr Valls said.

Police officers at an unauthorised protest against anti-police violence at the old harbour in Marseille, France, on Thursday. PHOTO: REUTERS

With security at its highest possible level, officers have been up in arms over attacks on the police during patrols in tough suburbs and during street demonstrations.

On Oct 8, a 28-year-old officer was seriously burned when he was attacked with a petrol bomb on the outskirts of the capital. He remains in a coma. The police have also been attacked in the Venissieux suburb of Lyon, where around 40 youths pelted them with petrol bombs.

Justice Minister Jean-Jacques Urvoas met police union representatives on Wednesday and pledged his "entire support to the police... who are exposed to significant and constant risks". The unions also met Interior Minister Bernard Cazeneuve, who urged calm, saying the government was supportive of the police and had recruited two-thirds of some 9,000 police staff after a drop of 12,000 under former president Nicolas Sarkozy.

The unions are now demanding a meeting with President Francois Hollande and calling for fixed minimum sentences for attacks on the police. Mr Hollande said yesterday he planned to meet police union leaders at the start of next week.

The government has accused Mr Sarkozy of cutting police jobs during his 2007 to 2012 presidency. Mr Sarkozy said violent crime was not about police numbers but insufficiently harsh treatment of criminals by the courts. "I understand the anger of the police," he told Europe 1 radio. "I've never seen such an erosion of authority in this country."