A motorcade which blocked an ambulance carrying a dying patient last year belonged to the former governor of the northern Leningrad region, police said.
"Restrictions on traffic were imposed in order to facilitate the passage of the convoy of Leningrad region governor [Valery Serdyukov]," St. Petersburg police said.
Serdyukov - no relation to Defense Minister Anatoly Serdyukov - was sacked by President Vladimir Putin last month.
Earlier media reports said the motorcade belonged to State Duma speaker Sergei Naryshkin, who was on an official visit in the region at the time.
The allegations appeared after the tabloid Lifenews.ru posted video footage of several black sedans traversing a motorway while traffic, including the ambulance, was blocked by police.
The patient in the ambulance later died on the hospital's threshold, Lifenews said.
