Officials in Rio have decided to step up their security measures for the Games in the wake of the recent attack in Nice. Brazil will increase the number of military troops to be deployed in and around Olympic venues and strategic sites to better ensure the safety of all who attend the mulit-sport showpiece. CCTV's Lucrecia Franco has more from Rio de Janeiro.

One hundred soldiers ran another drill on Tuesday at Rio's Guanabara Bay to test security plans just 17 days before the Rio Games kick off.

The drills began last week. They included a simulated anti- terrorism operation at a train station near one cluster of Olympic venues.

Another drill is at Maracana stadium, which will host the opening ceremony. Security concerns have increased following the truck attack in France.

Sergio Etchegoyen, head of intelligence service, said, "It is a difficult situation, a complex situation, because no one could have imagined that a truck could become a weapon of mass destruction."

In addition to the deployment of 85,000 police officers and soldiers - double the force used at the London Olympics - the new measures will include extra checkpoints, barricades, road blocks and traffic restrictions.

"Although Brazil doesn't have a history of terror attacks, the country is stepping up security in Rio to protect more than 10 thousand athletes, 500 hundred thousand visitors and the city's own six million residents," said Rio de Janeiro.

Many Cariocas, as Rio's people call themselves, have mixed opinions on safety.

Sandra Gomes, a Rio resident, said, "There are some threats appearing on the news about terrorism targeting some delegations and that of course is worrying."

Rio resident Marcelo Paes said, "I think it is going to be safe. Everything is going to be fine, because the army has taken over. But I am worried what will happen when the games end."

These simulations are just a part of Rio's security preparations for the Games that are relying mostly on international intelligence cooperation.

So far Brazilian authorities have denied Olympic accreditations to four people believed to have links to terrorism. Security officials have also recommended another 11,000 people be rejected, too.