Scuffles at May Day rally in Paris

French protesters and police have clashed briefly in Paris as thousands of people gather for a May Day march.

Authorities fear some troublemakers could join anti-government protesters and union workers.

Police used some tear gas to control a crowd near Paris' Montparnasse train station.

AP reporters observed groups of hooded people in black shouting anti-police slogans, mixing with other protesters wearing yellow vests or waving union flags.

French authorities warned "radical activists" may join the Paris demonstration and renew scenes of violence that marked previous yellow vest protests and May Day demonstrations in the past two years.

More than 7400 police have been deployed in Paris.

Yellow vests have joined the traditional May Day union march to show their common rejection of French President Emmanuel Macron's economic policies.