Spanish police on Monday arrested a prisoner accused of trying to radicalize and recruit fellow inmates to join Islamic State.
The man was originally from Morocco and was already serving time in a prison in Segovia, near Madrid, for crimes linked to violence against women, the police said in a statement.
Spain has stepped up efforts to stop citizens joining Islamic State this year, fearing people recruited to fight in Syria and Iraq could return to launch attacks at home.
Like other European countries it is on high alert since a wave of bomb and gun attacks by Islamic State militants in Paris on Nov. 13 left 130 dead, though the official security level in Spain was maintained at 4 after the attacks, on a scale of 5.
As of Nov. 20, Spain had been involved in the arrest of 91 suspects Islamic state militants at home and abroad, nearly double those detained in the whole of 2014, according to interior ministry data.