RIO DE JANEIRO -- Military police in Rio de Janeiro are stepping up security at the Olympics after a bus carrying journalists had two of its windows shattered by a projectile and a bullet flew into the stables area of the equestrian venue.

Two large windows on the media bus were shattered Tuesday by what Rio organizers said was a rock. But a passenger disputed the account, saying she was sure it was gunfire. There were no serious injuries.

Security has been a major concern surrounding the Olympics as Rio is plagued by rampant crime, including frequent murders, gun battles and muggings. Police near the Olympic beach volleyball venue in Copacabana found body parts on the shore last month, and an off-duty bodyguard for Rio's mayor was shot to death around the same time in an apparent mugging. Adding to the anxiety is terrorism fears about Islamic State.

Rio is deploying about 85,000 soldiers and police to secure the games, twice as many as London did four years ago. Soldiers in military fatigues and carrying guns have been a common sight around Olympic venues.

Security was visibly increased overnight on a media bus route toward a women's basketball arena, with three military vehicles and more troops holding guns along the way.

The equestrian venue has had two brushes with stray gunfire since the games started. As a result, officials are adding more security at the venue.

A bullet flew through the roof of a media tent at the Olympic Equestrian Center on Saturday. Officials said it had been fired from a hillside slum, and that the intended target was probably a security camera on a blimp.

A second bullet hit Wednesday near the stables around the same time investigators were arresting someone in the slum in connection with the first shooting. No one was injured in either episode.

"I can guarantee your total safety," said Gen. Luiz Ramos, chief commander for the first division of the Brazilian army. "We have reinforced security systems ... to provide more security."

The entire competition venue is situated on military land and gunshots could be clearly heard throughout the day during the dressage competition. Riders said they and the horses were not bothered by the noise, but Ramos said authorities ordered a halt to the training exercises.

Newton de Oliveira, an independent security expert with no ties to the organizers, said the fact remains that Rio is still a violent city despite the beefed-up patrols.

"The level of violence is the same despite the deployment of forces," he said. "You can see that areas downtown and near the beaches -- the security forces have made crime drop some, but the city in general is just as dangerous."

Passenger Lee Michaelson described a panicked scene on the media bus as the glass shattered and people ducked for cover. Michaelson insisted she heard gunshots.

"I know what a gun sounds like," said Michaelson, who identified herself as a former Air Force officer covering the games for a women's basketball website. "It was the sound before I ever saw the glass (shatter) or anything."

Rio police were adamant that it wasn't gunfire, and they expressed confidence in their ability to get to the bottom of what happened.

"There were no shots, the forensics were made on the bus, I have pictures and I can show them," said Rio police Investigator Carolina Salomao. "If there were a shot it would have gone through. There was not that so that theory has been completely discredited."

 

AP writer Adriana Gomez Licon contributed to this report