Vyacheslav Yaroshenko was found unconscious with a head wound at the foot of a staircase in the building where he lives in the early morning hours of April 30.
The CPJ quotes Yaroshenko's deputy, Sergei Sleptsov, as saying Yaroshenko was hospitalized with skull and brain trauma. Doctors performed two surgeries and Yaroshenko was in a coma for five days.
Sleptsov says Yaroshenko was taken off a respirator on May 5, but he remains unconscious.
Sleptsov told the CPJ that he believes Yaroshenko was assaulted in retaliation for his journalistic activities.
Police first said Yaroshenko had been injured in a fistfight on a local street. Police later said Yaroshenko had come home drunk and injured himself by falling down the stairs in his building.
The Russian news agency RIA Novosti quoted a spokesman for the Rostov region's Department of Internal Affairs as saying police were not looking into the possibility that Yaroshenko was attacked.
"The trauma sustained by the journalist exhibits an exclusively domestic character," an unnamed spokesman said.
"We are disturbed by the high number of critical journalists attacked and injured in Russia in what law enforcement calls 'accidents,' " Nina Ognianova, CPJ's Europe and Central Asia program coordinator, said in a statement.
“The conflicting accounts provided by local authorities in Vyacheslav Yaroshenko’s case reinforce our skepticism. Federal authorities should launch an independent investigation into the case,” she said.