French police have released three of the 12 suspects arrested Friday in an anti-terror sweep following the attacks in Paris by Islamic extremists that killed 17 people and put Europe on high alert. 

Paris prosecutor spokesman Denis Fauriat said nine other suspects detained Friday will have their interrogations prolonged by 48 hours, a step allowed under France's tough anti-terror laws.

Police in France, Germany and Belgium have arrested dozens of suspects in recent days as part of the anti-terror sweep sparked by last week's bloody spree in and around Paris, in which brothers Said and Cherif Kouachi and their friend Amedy Coulibaly killed 17 people at the satirical newspaper Charlie Hebdo, a kosher grocery, and elsewhere. (AP)