Police opened fire with live ammunition Saturday when protesters cornered them at a Basque independence march, officers said.
The confrontation in the northern city of Bilbao injured at least 20 people, including two people hit by real bullets and two people hit by rubber bullets, police said.
About 10,000 people took part in the march, shouting slogans supporting independence for northern Spain’s three Basque provinces and backing the armed Basque group ETA.
Police said six officers were among the injured. None of 20 injured was believed to be seriously wounded.
ETA has admitted killing nearly 770 people since it took up arms in 1968. Saturday’s demonstration followed the killing of three people this week, including a Supreme Court judge, in attacks blamed on ETA.
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