"This country is in no mood for taking to the streets," Pin said.
One of the strike's most noticeable effects was on public transportation, with unions guaranteeing only around 30 percent of normal service at rush hour times. The main airline, Iberia, canceled 65 percent of its flights.
By midmorning, 402 flights had been canceled, National airport operator AENA said. Minimum services decreed by law ensured that 1,675 flights would operate — less than half of the average daily amount of more than 4,500 flights.
British Airways said its flights were operating normally but advised passengers to check the status of their flights before heading to the airport. TAP Air Portugal said it canceled just over half of its 27 scheduled return flights to Spain.
The union UGT said virtually all workers at Renault, SEAT, Volkswagen and Ford car factories around Spain, and at other industrial, mining and port facilities, honored the strike during the overnight shift.
Diaz, the Interior Ministry official, said a Molotov cocktail was thrown at a police car in the eastern city of Murcia. Of six people injured, one was a police officer and five were civilians. She did not specify where or how these people were hurt.
Spanish National TV showed footage of police in Madrid on horseback accompanying buses trying to leave a parking garage, and scuffling with a picketer. Regional TV stations in Andalusia in the south, Catalonia in the northeast and Madrid were off the air because of the strike.
Barry Hatton in Lisbon, Portugal contributed to this report.
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