Turkey's official news agency says Istanbul police have detained 36 people as alleged members of the Islamic State group.

The Anadolu news agency reported Saturday that anti-terror police conducted simultaneous raids at 15 different addresses in Istanbul to apprehend five suspects who allegedly had travelled to Iraq and Syria for IS.

The news agency says 31 of the people detained are foreigners. There was no information on their nationalities.

Several deadly attacks in Turkey that killed more than 300 people since 2015 have been blamed on IS.

Along with combatting the extremist group's cells inside its borders, Turkey launched a military operation in northern Syria in August 2016 to clear the border zone of IS members after a suicide bomb ripped through a street wedding in Turkey's Gaziantep province.