Opposition leader Alexei Navalny’s lawyer has appealed to the prosecutor general’s office to investigate the whether officials sanctioned an attack on the politician last April.

Navalny was hospitalized in April after a member of the SERB nationalist group sprayed him with green antiseptic, causing a chemical injury to his eye. The opposition leader has been barred from running in next year’s presidential elections due to embezzlement convictions his supporters say is politically motivated.

A former member of SERB recently claimed in an interview with the opposition-leaning Dozhd TV network that Major Alexei Okopny of the Interior Ministry's Anti-Extremism Center directed SERB’s attacks on Navalny and his supporters.

Navalny's lawyer Vadim Kobzev told the prosecutor general’s office that police have for the third time halted their investigation into the attack, claiming they could not identify the assailants, the Interfax news agency reported Wednesday.

"Navalny has not been recognized as a victim and has not been questioned,” Kobzev told Interfax.