There was a scare at the Olympic Equestrian Center as a military bullet pierced the roof of the media tent and landed on the floor.
The incident occurred during the lunch break at the dressage event Saturday. The competition was not disrupted and nobody was hurt.
The bullet landed inches from one of the media tables at the end of the room where the press conferences are held, leaving a clear hole in the roof. An official statement is expected shortly.
The arena is located near a military compound.
The incident was immediately reported and the bullet collected, while Brazilian military was swiftly at the scene.
There was another security scare in Rio Saturday when a small blast was heard near the finish line of the men's cycling road race. An officer assigned to the event told The Associated Press that it was a controlled explosion of an unattended bag.
And Friday night, eyewitnesses said a man was shot dead near the Maracana Stadium in Rio de Janeiro after the Olympic opening ceremony. Associated Press photographers reported hearing loud multiple gun shots, forcing games volunteers and others leaving the ceremony to duck for cover behind cars. Paramedics were later seen treating the victim as blood poured from his body onto the road.