Second bullet in Rio equestrian centre

A man has been arrested in relation to a bullet that tore through the media tent at the equestrian complex at the Rio Olympics.

The arrest came on Wednesday as a second bullet was also found near the stables at the Deodoro venue, in Rio's northwest.

A police commander told a media briefing that no one was shooting directly at the venue.

Police said previously they believed the bullet that pierced the roof of the media facility on Saturday was fired by a gang member trying to shoot down a police blimp or drone.

The commander said the man was arrested about two kilometres from Deodoro and there was no danger that anyone was intentionally targeting the Olympic venue.

"We can guarantee your safety. You are totally safe," he said.

The bullet found on Wednesday was located by a policeman close to a fence by the stables.

The commander said a decision had also been made to suspend training at a nearby military base.

He said that training was the reason shots could be heard at times during the day.