Last week, Prosecutor Hasan Yilmaz submitted a petition of objection to the court asking for the individuals to be re-arrested.
Among those suspects released was Ekrem Dumanli, editor-in-chief of the Zaman daily newspaper. He was released on condition that he would not travel outside Turkey.
On Dec. 14, a police operation was launched against senior media figures and police officers in 13 provinces across Turkey for allegedly being affiliated with what the government describes as the "parallel state," a purported group of bureaucrats embedded in the country's institutions, including the judiciary and the police.
More than 20 suspects were taken into custody for being allegedly linked with U.S.-based preacher Fethullah Gulen and his so-called Hizmet movement.
In December 2013, an anti-graft probe targeted several high-profile figures, including the sons of three former government ministers as well as leading Turkish businessmen.
The government denounced the probe as a "dirty plot" constructed by a "parallel state."