Police say the Second Severn Crossing has reopened westbound following a blockade by Kurdish protesters.
The protest caused the Severn Bridge to shut after demonstrators stopped their cars in the middle of the motorway.
Around 15 people stopped traffic and held up a Kurdish flag half way across the motorway bridge between England and Wales.
Eyewitnesses say the group were yelling anti-Turkish slogans. The demonstration started at 1.30pm and lasted for an hour.
Watch this eye-witness video taken from a vehicle passing the protest.
A police spokeswoman has said motorists were not impressed by the demonstration holding up traffic.
The bridge was closed for a while while we dealt with the situation and traffic was diverted across the old Severn Bridge.
"The second crossing has since reopened in both directions.
Motorists caught up in the backlog of traffic were unimpressed.
Police have yet to confirm if there have been any arrests and the roads are now clear.
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