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Highway patrols from Spain's Civil Guard stopped coaches on their way to Madrid for Saturday's pro-independence demonstration. Protesters reported these "arbitrary actions" in messages and images uploaded to social media.

Along the main route to Madrid there were several Civil Guard checkpoints. Shortly after entering Aragon from Catalonia, vehicles were stopped at Bujaraloz and then later at the Pina de Ebro tollbooths. In some cases, they even searched the luggage compartments.

Translation:
"The Civil Guard is already starting to do its thing and stop coaches on their way to the Madrid rally. And drivers have been fined. The anger they must feel to see so many 'estelada' flags together. They are acting arbitrarily and as a #PoliticalPolice.  #ThisIsTheRealSpain"— albertdmcat

"Well it wasn't fake news. They're now inspecting our luggage compartment, to make sure there's no Fairy detergent."
"The excuse is that we crossed a solid line. We've been stopped for 20 minutes. And just wait." — Lydia  

In some cases, say the occupants, Civil Guard officers asked to see the all the coach drivers' documentation.

"The Civil Guard has temporarily stopped a bus in the Pina de Ebro area and they are asking to see documentation, including the 'service contract' form, even though it's legal to contract a coach service by phone. They don't like us filling Madrid but we won't simply shut up." — ANC Balaguer

In fact, some of the images uploaded show several buses stopped at once by the Civil Guard, an action which seems unusual as part of a random check policy.

"The Civil Guard stopping coaches heading for Madrid. They suspected the vehicles were loaded with Fairy detergent, but it was worse, they were carrying yellow ribbons."— Joan Mani (Sabi Strubel) ​

In at least one case, a driver was given a ticket by a Civil Guard patrol, with a €100 fine that was paid by all passengers chipping in a little more than a euro per head: