A stand-off between Canadian police and protesters blocking a key bridge to the US continues, more than seven hours after authorities moved in.

Demonstrators opposing the government’s strict pandemic restrictions occupied the Ambassador Bridge for the fifth straight day on Saturday.

The bridge, North America’s busiest land border crossing, has no traffic flowing after about 15 trucks, cars and vans blocked traffic in both directions, choking the supply chain for Detroit’s car makers.

“We urge all demonstrators to act lawfully & peacefully,” Windsor Police said in a Twitter post, asking commuters to avoid the areas affected by the demonstrations. 

The police action came more than 12 hours after a court order to end the blockade came into effect.

Police in black uniforms with yellow vests moved behind the protesters’ vehicles and, accompanied by police cruisers, slowly advanced on protesters, pushing them back from the bridge entrance. 

The number of demonstrators had thinned to roughly two dozen early on Saturday from about 200 on Friday night.

“We are opening up this intersection to traffic. If you fail to comply with our instructions you will be arrested,” police told the crowd via a loudspeaker.

Protesters were seen moving back in a noisy but peaceful retreat, dismantling tents and barbecues. 

While police have successfully pushed back protesters from the foot of the Ambassador Bridge, many more people were streaming into the area.

The “Freedom Convoy” protests, started in the capital Ottawa by Canadian truck drivers opposing a vaccinate-or-quarantine mandate for cross-border drivers, entered its 16th day on Saturday.

It has morphed into a wider protest against COVID-19 curbs, with people joining in with smaller vehicles, including cars, vans and utes.

Ottawa Police said on Saturday they were waiting for reinforcements to end the “unlawful occupation”. 

Ontario Premier Doug Ford declared a state of emergency starting on Friday at midnight, but demonstrators “exhibited aggressive behaviour towards law enforcement”, police said.

Protesters in Ottawa also tore down a fence that had been put around the National War Memorial on Saturday.

Canadian police have said the protests have been partly funded by US supporters and Ontario froze funds donated via one US platform, GiveSendGo, on Thursday.

The protests have inspired similar convoys and plans in the United States, France, New Zealand and Australia.

In Paris, French police fired tear gas at demonstrators on the Champs Elysees avenue on Saturday shortly after a convoy carrying protesters against COVID-19 restrictions made it into the capital.

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