Istanbul, Mar 25 (IANS): Turkish police detained 18 suspects in the country's biggest city of Istanbul for their alleged ties to the Islamic State (IS) terror group, local media reported.

Police forces and special operation teams launched simultaneous operations on Wednesday at 15 addresses to capture the suspects, Xinhua news agency quoted the local media as saying.

Those targeted in operations, including 16 foreign nationals, illegally crossed into Turkey after spending "a long time" in conflict zones in Iraq and Syria.

Many organisational documents and digital materials were also seized during the raids.

Last week, at least eight more suspected IS members were detained in the city for their alleged ties to the terror group, according to press reports.

The IS has conducted a spate of deadly attacks in Turkey since 2015.

Since then, Turkish counter-terrorism units conduct operations against the group members in the country.