Clashes erupted between protesters and police in French Guiana on Thursday night during a visit by French President Emmanuel Macron.
Petrol bombs were thrown and police responded with tear gas in the French overseas territory’s main city Cayenne, amid anger over social deprivation.
The territory in South America has 23% unemployment – more than double the rate of mainland France.
A huge strike and road blockade gripped French Guiana earlier this year.
On Thursday police arrested five protesters during clashes after a demand for an immediate meeting with Mr Macron had been rejected.
In March protesters occupied the space centre at Kourou, used by France and the European Space Agency for launching satellites.
Protesters complained that money was being poured into prestige space projects while the welfare of ordinary people in French Guiana was neglected.
The protest movement has the slogan Pou Lagwiyann Dekole, which is Creole for “Let Guiana take off”.
Mr Macron, accompanied by European Commission President Jean-Claude Juncker, is set to visit Kourou on Friday.
He has pledged to commit €1.08bn (£0.96bn; $1.26bn) in emergency funding to French Guiana under a deal reached by the previous Socialist government.
There is discontent among the territory’s 254,000 residents over an influx of illegal immigrants and neglect in the healthcare and school systems.