Reporter disputes Rio security claims that rocks, not bullets were to blame for bus attack

The projectiles that struck a bus carrying journalists through Rio de Janeiro last nightwere stones, not bullets, according to the security chief for the OlympicGames but reporters who were on board seem less than convinced.

Games security chiefLuizFernandoCorreasaid Wednesday the bus windows that shattered Tuesday night slightly injuring two of the 12 people who were on board were not hit by gunfire.

"First findings of the forensic study confirm that the bus was hit by a rock,which is also worrying and terrible,"Correa said at a news conference.

Brazil has some Olympic-quality rock throwers. Lee Michaelson, retired U.S. Air Force captain

But witnesses said at the time they heard shots. One of them,a retired U.S. Air Force captain who now writes about women's basketball, was on the bus as it went throughthe Rio suburb ofBarradaTijuca.

"I know what a gun sounds like," LeeMichaelson toldBritain's Press Association at the time.

"It was the sound, before I ever saw the glass [shatter] oranything."

Another journalistsaid he heard "a popping sound" before something hit the windows.

The holes "looked like bullet holes," said photographer David Davies.

Michaelsonseemed skeptical duringWednesday's news conference.

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"Assuming for the moment that Brazil has some Olympic-quality rock throwers to have been able to hit not onebut two windows, that quickly, at upper-body height on a moving bus, moving that quickly down the road, we'll give it toyou for the moment what I'd like to know is about the things that can be prevented," she said toCorrea.

Why, she asked, did the driver stop the bus, rather than drive to a secure location? Why were the interior overhead lights left on during the trip? And why was there no first-aid kit on board?

Michaelsonhadsaid earlier there was nomedical help waiting when the bus returned to Olympic Park,despite some passengers being injured and bleeding.

Police escort

The Rio organizing committee said earlier the driver heard a noise from inside the bus, which he thought was photography equipment falling down.

When he checked his rear-view mirror, he found the journalists were lying on the ground. He stopped when he saw a police car.

"At this time, he realized that two windows on the same side of the bus were broken," the committee said in a statement. "He resumed the route under the escort of the police car and the broken windows began to give way further."

• Robberies prompt calls for increased security in Rio

The incident raises more concerns about security at the Games.

On Saturday, a stray bullet flew through the roof of a media tent at the Olympic equestrian centre. Officials said it had been fired from a hillside favela but said the Games had not been targeted. Organizers said the intended target was probably a security camera on a blimp.

Rio is deploying about 85,000 soldiers and police to secure the Games, twice as many as London did four years ago.