By Daren Butler
ISTANBUL (Reuters) - Dozens of Turkish police including high-ranking officers were detained on Tuesday, accused of spying and illegal wire-tapping of Prime Minister Tayyip Erdogan 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 Erdogan is standing.
The operation follows a stream of purges targeting the police, judiciary and state institutions this year which government critics have condemned as a symptom of Erdogan's tightening grip.
Concern about his autocratic style has been fueled by his intention to boost the powers of the presidency if he is elected, a plan he reiterated late on Monday.
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 pretence to tap the phones of Erdogan, 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 Salihoglu 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 Atayun was quoted as saying by CNN Turk 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 Erdogan to describe members of the police, judiciary and other institutions loyal to U.S.-based Islamic cleric Fethullah Gulen, whom he accuses of being behind a plot to oust him.
The investigation looked set to widen, according to comments from Erdogan, who spoke briefly to reporters in parliament about the arrests and said the government was monitoring the case.
One reporter said the operation was being characterized as a "cleansing of the parallel structure" and asked if it could spread to other areas.
"That's how it looks. Of course," Erdogan replied.
Erdogan accuses Gulen's Hizmet ("Service") network of concocting the scandal by illegally tapping thousands of phones and leaking manipulated recordings on social media.
His aides had made clear the fight against Hizmet would continue in the run-up to the Aug. 10 election, the first direct vote for the presidency, for which Erdogan is the clear 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 Gulen's influence.
Gulen, who has lived in self-imposed exile in Pennsylvania since 1999, denies plotting against the government.
(Additional reporting by Ece Toksabay; Editing by Nick Tattersall and Hugh Lawson)