Ankara: Turkish authorities on Tuesday arrested at least 25 police officers in the latest nationwide swoop to detain suspects alleged to have illegally wiretapped key government figures including Prime Minister Recep Tayyip Erdogan, reports said.

Police conducted raids in 12 cities across Turkey, including Istanbul as well as the western province of Izmir, as part of the investigation into the allegations of espionage and illegal wiretapping, the private Dogan news agency reported.

The swoop was the third such round-up since July of suspects in a probe which has resulted in dozens of arrests and raised tensions as Erdogan prepares for his inauguration as president on August 28.

The probe is linked to last year’s stunning corruption allegations against Erdogan and his inner circle — vehemently denied by the premier — that were based on wiretapped telephone conversations.

In a statement, Izmir governor’s office said the arrests centred on wiretapping allegations involving the Izmir police department between 2010 and 2013.

The suspects were facing a series of charges, from forming a crime ring to forging official documents and violation of privacy, Dogan said.

Among the detainees was former Izmir police intelligence deputy head Hassan Ali Okan. He was removed from his position after what appeared to be a broader government purge of Turkey’s police in the aftermath of the corruption allegations in December.

The government of Erdogan has embarked on a massive purge targeting the police and judiciary, believed to be filled with loyalists of US-based Muslim cleric Fetullah Gulen who it blames for the allegations.

Gulen is a former ally of Erdogan’s Islamic-rooted Justice and Development Party (AKP) but has become his arch-foe after the December corruption scandal.

As with the two previous raids, the details of the swoop were leaked by a shadowy Twitter user named Fuat Avni before it was even carried out. The government has repeatedly moved to block his account.