(MENAFN- Gulf Times) Police on Thursday announced a swoop on a European jihadist network that was allegedly planning to kidnap diplomats and carry out attacks to try to spring its leader out of detention in Norway.

Seventeen arrest warrants were issued and 13 people were detained in Italy, Britain and Norway, according to Eurojust, the EU's Judicial Cooperation Unit.

The other wanted suspects were believed to be fighting in Iraq or Syria for the Islamic State (IS) group, according to Italian police, who led the operation.

Investigators said the network was trying to free Norway-based fundamentalist preacher Najmuddin Ahmad Faraj - also known as Mullah Krekar - who is listed as a terrorist by the US and UN.

Krekar has been serving time since 2012, apart from a brief period at the beginning of this year. He was freed in January after completing his sentence for intimidation and death threats, but rearrested at the end of February for inciting crime.

Giuseppe Governale of the Italian police's Special Operations Group told journalists the operation had "dismantled an integrated cell that included - in addition to Italy - Britain, Norway, Finland, Switzerland and Germany".

The sting on the cell, which was "affiliated with IS", was "the most important police operation in Europe in the last twenty years".