Turkish security forces have detained more than 200 people in a sweeping operation targeting suspected members of the Islamic State group and several outlawed far-left organisations, as Ankara tightens security ahead of an upcoming NATO summit in the capital.

The Ankara prosecutor’s office confirmed that 209 suspects were taken into custody across the city, with warrants issued for dozens more who remain at large. The coordinated raids were carried out by counterterrorism units in multiple districts, following intelligence reports that extremist networks were seeking to exploit the high-profile diplomatic gathering.

Authorities said the majority of those detained, 185 individuals, are accused of belonging to far-left groups designated as terrorist organisations under Turkish law. Among them is the Revolutionary People’s Liberation Party-Front, or DHKP-C, a Marxist-Leninist group that has claimed responsibility for a series of attacks in Turkey over the past decades, including assaults on security forces and diplomatic missions.

Officials indicated that the operation also targeted suspected Islamic State cells believed to be involved in recruitment, financing and logistical support. While no imminent plot was publicly disclosed, security sources described the arrests as part of a broader effort to neutralise potential threats before world leaders arrive for the NATO meeting.

In a parallel move, the Ankara governor’s office announced a blanket ban on all demonstrations and public gatherings in the capital for the duration of the summit. The prohibition, which took effect days before the event, is framed as a precaution to prevent unrest, protect visiting delegations and reduce the risk of attacks on symbolic targets.

The NATO summit is expected to draw leaders and senior officials from all 32 member states, including the president of the United States, placing Ankara at the centre of global diplomatic attention. Turkish authorities have historically intensified security operations ahead of such events, citing the country’s past experience with both jihadist and leftist militancy.

Analysts note that the latest arrests underscore Ankara’s dual-front counterterrorism strategy, aimed at dismantling both Islamist and radical left-wing networks. Human rights groups, however, have previously raised concerns that broad terrorism laws and mass detentions can sweep up political activists and critics alongside genuine security threats.