French riot police clashed with uniformed firefighters at protests in Paris on Tuesday, in extraordinary scenes where police used batons and shields against crowds of angry fire officers in helmets.

Thousands of firefighters held a demonstration in the French capital, as part of long-running protest movement asking for better pay and conditions, including an increase in their hazard bonus which has not changed since 1990.

Some firefighters set their uniforms alight as a symbolic gesture before colleagues put out the fires. But as a group of fire officers attempted to lead their demonstration into a sidestreet, riot officers pushed them back. Teargas was fired and scuffles broke out.

Facebook Twitter Pinterest Firefighters simulate setting themselves on fire during the protest in Paris. Photograph: Charles Platiau/Reuters

Videos of the clashes went viral on social media amid growing pressure on the government over French police tactics of crowd control at demonstrations.

A number of recent videos showing what appeared to be unjustified police violence at other demonstrations have sparked outrage on social media. After scores of serious injuries from police weapons during the gilets jaunes anti-government protests last year, and complaints of heavy-handedness at pensions protests, lawyers have begun accusing the French president, Emmanuel Macron, of presiding over the most heavy-handed approach to street demonstrations in France since the protests of May 1968.

More than 200 alleged abuses related to police handling of the yellow vest protests have been signalled to the General Inspectorate of the National Police watchdog – and the media estimate there have been been dozens of serious injuries among protestors, including lost eyes and at least five severed hands.

For months, the government has held firm, defending police tactics and policy but, as local elections approach this spring, Macron’s tone has begun to change.

The president warned last week that the “unacceptable behaviour” of some officers risked undermining the “credibility and dignity” of the force. But he also denounced the violence of some extremist protesters, who have hurled paving stones and other projectiles at security forces during protests.

The French interior minister, Christophe Castaner, this week announced that France would withdraw from use of one particular brand of explosive teargas grenade used by riot police, which has been blamed for injuring numerous protestors. But rights groups and lawyers immediately criticised the government for a “political announcement”, saying that this particular model of grenade had already been discontinued by manufacturers. They said other equivalent grenades would remain in use by French police to the same effect.

The “sting-ball” grenades contain 25g of TNT high-explosive. France is the only European country where crowd-control police use such powerful grenades, which deliver an explosion of small rubber balls that creates a stinging effect as well as launching an additional load of teargas. The grenades create a deafening effect that has been likened to the sound of an aircraft taking off.

One French lawyer handling several cases of alleged police violence said: “Withdrawing one type of grenade doesn’t change anything, other grenades which are still in use do the same thing.”

Marion Guémas from Action by Christians Against Torture, which has campaigned to end the use of all such grenades, said: “We observe that the use of certain weapons is not appropriate for maintaining public order and can lead to an escalation in violence”.

She called for a review of the French police’s use of weapons in crowd-control.