A jihadist network spanning 17 prisons had attempted to radicalize inmates and establish a "prison front," according to authorities. Several of the inmates were due to be released, posing a potential security risk.
Spain's Interior Ministry on Tuesday said police had dismantled a network of jihadists operating in more than a dozen prisons across the country.
"Although the investigation began by focusing on an inmate in a particular prison, to date the illegal activity of the group extended to 17 prisons, which account for 55 percent of jails that house prisoners linked to jihadist terrorism," the ministry said.
The network attempted to radicalize other inmates in order to establish a "prison front." A source at the interior ministry told AFP news agency that although there was no "concrete plan" to carry out an attack, the ring had created a "belligerent state of mind towards prison staff."
The ring also attempted to bypass mechanisms aimed at monitoring and preventing radicalization within Spain's prison system.
"The very existence of the group is viewed as a potential security risk, even more so given the upcoming release of several of the inmates who were targeted by the investigation," the ministry said.
Spain's Interior Ministry noted that the operation to break up the IS-affiliated ring was the first of its kind in Europe and brought together law enforcement agencies with those that manage prison facilities in the country.