MADRID (Reuters) - Spanish police on Wednesday arrested nine suspected members of the Basque separatist group ETA in the second major blow in two days against the guerrillas, state radio reported. The radio cited law enforcement sources as saying the latest detentions in the Basque region marked the break-up of ETA‘s so-called Donosti Commando, one of its most dangerous units. The arrests came the day after French police captured the head of ETA‘s military wing in Paris. The nine suspects, who had been under lengthy police surveillance, were taken into custody in a series of raids across the Basque country of northern Spain. The arrests followed that of Jose Javier Arizcuren, alias "Kantauri", considered ETA‘s military chief, and five of his alleged lieutenants who had been using France as a safe haven. Arizcuren, 40, is accused of ordering or carrying out at least 20 murders and numerous bombings since joining ETA in the early 1980s. The latest series of arrests was the strongest action taken against ETA (Basque Homeland and Freedom) since it declared a unilateral ceasefire last September in its 30-year fight for an independent Basque homeland.