NEW : Spain 's Spanish police says the man 's current role in the murder is under investigation . The police will continue to pursue ETA members wherever they go , Rubalcaba says . Members of ETA allegedly tried to kill Spain 's King Juan Carlos when he attended the inauguration of the Guggenheim Museum in Bilbao , Spain , in October 1997 . The man is suspected of being a member of the Basque separatist group ETA . The alleged assassination attempt occurred in Madrid .
NEW : Spain 's Spanish police says the man 's current role in the murder is under investigation . The police will continue to pursue ETA members wherever they go , Rubalcaba says . The man is suspected of being a member of the Basque separatist group ETA . The alleged assassination attempt occurred in Madrid .