The controlled explosion of a suspect package at the finish line of the men's Olympic road race was carried out as a precaution.
Omnisport understands that the loud bang heard with 70 kilometres of the race to go was actually a false alarm.
As the elite cyclists made their way around the 241.5-km route, the explosion was heard close to Copacabana beach - where the race is due to finish.
Brazilian security services were seen investigating an area close to the press tribune as the peloton moved into the final 70km to race, with the explosion coming soon after.
However, concerns regarding the package were quickly dampened with officials suggesting there was nothing to worry about.
A Rio 2016 spokesman told The Guardian: "The security services found a suspicious package close to the cycle road race finish line in Copacabana and as a precaution decided to perform a controlled explosion.
"There is no impact to the race, which is ongoing."