Moscow police say a taxi driver whose car plowed into pedestrians and injured soccer fans near Red Square reported that he fell asleep and confused his brake and gas pedals.
Police made the statement on June 17, after releasing a video in which the driver, who was identified as being Kyrgyz, said he had dozed off after driving for 20 hours straight and that he wasn't drunk.
It was impossible to determine whether the man had been pressured to speak.
Video of the June 16 incident posted on social media showed the car veering out of standstill traffic and accelerating onto the sidewalk, mowing down pedestrians. He then flees the car as bystanders attempt to apprehend him.
Moscow city health officials said eight people were injured in all.
Moscow Mayor Sergei Sobyanin also said in a post to Twitter that the driver "lost control" of the car in what he called an "unpleasant incident."
Sobyanin added that he was overseeing authorities' response.
Russia has instituted strict security measures nationwide as it hosts the World Cup soccer tournament, taking place in 11 cities over the next month.
Among the security concerns has been the possible use of vehicles as weapons.