Russian prosecutors are probing the hospitalization of two prison officials charged over the high-profile death of lawyer Sergei Magnitsky.
The deputy governor and chief doctor at Moscow's notorious Butyrka prison were charged with negligence causing death last month.
Magnitsky died in 2009 after accusing Russian officials of a huge tax fraud scheme.
He was arrested in November 2008 on charges of tax evasion and detained in Butyrka pending trial.
Magnitsky, who was working on behalf of a British investment company, Hermitage Capital Management, died a year later. In July, the Kremlin's rights body reported to President Dmitry Medvedev that Magnitsky's death was likely the result of beatings and the refusal of medical assistance.
Vladimir Markin, spokesman of the Investigative Committee of the Prosecutor-General's Office, said the investigation into the case is almost complete, but the pair's hospitalization "prevents them from taking part in investigative and procedural activities."
"The prosecution is now probing the circumstances and the gravity of the illnesses of the accused," Markin said.