MADRID (AP) — A delegation including American rights activist Angela Davis has been turned away from a Spanish prison where it tried to visit imprisoned Basque separatist politician Arnaldo Otegi.

Davis, Spanish rock musician Fermin Muguruza and Basque politician Amaia Izko tried to visit Logrono prison where Otegi is serving a 10-year sentence after being convicted in 2009 of attempting to resurrect the banned Batasuna separatist party.

Davis, a former Black Panthers member acquitted of murder and kidnapping charges in California in 1972, said she "was a political prisoner" once and had signed a petition called "Free Otegi, Free Them All," which was presented to the European Parliament.

Backers include former Uruguayan President Pepe Mujica and anti-apartheid campaigner Desmond Tutu, she said.