Turkey's official news agency announced Sunday that police have detained 47 university staff members in a probe into the failed coup attempt last July.

Anadolu, the state-run news agency, said police also have outstanding warrants for 25 others. Eight of those detained work at Bogazici University, based on the European side of Istanbul; the 39 others work at Istanbul Medeniyet University, on the Asian side of the city.

Reuters reports that 19 of those ordered arrested at Medeniyet are professors on the medical faculty.

Authorities blame the July 15 uprising on Fethullah Gulen, an elderly cleric who has been living in Pennsylvania since the late 1990s. Anadolu said police had made the arrests in early-morning raids, and that some of the suspects were using a messaging app called ByLock.

The government believes that Gulen's followers use the app to communicate. Last year, security experts told Reuters the app seemed to have been built by amateur software developers, and that it left important user information unencrypted.

The arrests came the day after CHP, Turkey's main secular opposition party, completed a 280-mile march from the capital city of Ankara to Istanbul. The party's leader, Kemal Kilicdaroglu, told huge crowds in Istanbul that the rally marked "a new birth."

"We marched for justice, we marched for the rights of the oppressed. We marched for the MPs in jail. We marched for the arrested journalists," Kilicdaroglu said, according to the BBC. "We marched for the university academics dismissed from their jobs. We marched because the judiciary is under a political monopoly."

The march and the rally were permitted by the government, though NPR's Peter Kenyon reports that President Recep Tayyip Erdogan said the marchers were aligning with terrorists intent on damaging the country.

Saturday marks the anniversary of last year's attempted coup, and the ruling party is organizing large and widespread events commemorating the day and the 250 people who died resisting the uprising, Peter reports.

More than 50,000 people have been arrested in crackdowns, according to the Associated Press.

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