Istanbul, Reuters—Dozens of police, including high-ranking officers, were detained in Turkey on Tuesday, accused of spying and illegal wire-tapping of Prime Minister Recep Tayyip Erdoğan and his inner circle in what the chief prosecutor said was a concocted probe of an alleged terrorist group.

The former Istanbul anti-terror police chief, himself among those detained and led away in handcuffs, said the incident was entirely political, coming just a few weeks ahead of a presidential election in which Erdoğan is standing.

Police conducted raids in 22 provinces, and officers involved in a separate government corruption probe which emerged in December and led to the departure of four ministers were among those detained, Turkish media reported.

The officers were accused of making up an investigation into an alleged terrorist group named “selam-tevhid” as a pretense to tap the phones of Erdoğan, ministers and the head of the national intelligence agency.

“The order was given for the capture and detention of 76 police officers who were investigating the group named selam-tevhid but whose actual aims were spying,” Istanbul chief prosecutor Hadi Salihoğlu said in a written statement.

He said the selam-tevhid case, targeting 251 people, had been dismissed due to a lack of evidence after a three-year investigation during which 2,280 people were wire-tapped.

Fifty-two of the 76 officers have so far been detained, and Turkish media published photos of former anti-terror police chiefs being led away in handcuffs by their colleagues.

“We handed ourselves in and they handcuffed us behind our backs. It’s completely political,” former Istanbul anti-terror police chief Yurt Atayün was quoted as saying by CNN Türk as he was detained.

The order was also given for the arrest of another 39 suspects, of whom 15 have so far been detained, over the wiretapping of around 250 people, including deputies, judges, journalists and senior bureaucrats, allegedly on the grounds of being members of an illegal group, the statement said.

It did not specify whether this was the same “selam-tevhid” group.

Turkish media described the police raids as targeting a “parallel structure” within the state, a term coined by Erdoğan to describe members of the police, judiciary and other institutions loyal to US-based Islamic cleric Fethullah Gülen, whom he accuses of being behind a plot to oust him.

Erdoğan accuses Gülen’s Hizmet (“Service”) network of concocting the scandal by illegally wiretapping thousands of government phones and leaking manipulated recordings on social media.

His aides had made clear the fight against Hizmet would continue in the run-up to Turkey’s first direct presidential election on August 10, in which Erdoğan is the front-runner.

Thousands of police officers and hundreds of judges and prosecutors have already been reassigned and senior officials in state institutions dismissed since the investigation, in what is seen as a government drive to wipe out Gülen’s influence.

Gülen, who has lived in self-imposed exile in Pennsylvania since 1999, denies plotting against the government.