Brazil arrests group plotting 'acts of terrorism' before Olympics

Brazil's federal police began an antiterrorism operation early Thursday, just over two weeks before the Olympics start in Rio de Janeiro, a justice ministry source told Reuters.

The source said that federal police had arrested members of a group that was preparing acts of terrorism.

It was unclear where the operation was taking place or what the specifics of the operation were.

Amid the myriad issues facing the Rio games, slated to start August 5, the security has come to the fore in the days since an attack in Nice, France, that left more than 80 people dead.

Brazilian officials had already banned trucks from parts of Rio to reduce congestion and make emergency responses easier. In the wake of the Nice attack, in which a man drove a truck down a promenade, killing 84 people, Brazilian officials reconvened to assess the city's security preparations.

"I have no doubt that the Brazilian authorities and the International Olympic Committee have taken note of what happened, they're checking to see if they've incorporated that thinking into their plans," Jim Hutton, chief security officer at travel-risk-management company On Call International, told Business Insider.

"This is the kind of thing that makes you pause and go back and refresh what you're doing based on what is a pretty simple threat: One guy with one truck. But look at the damage that he did," Hutton said.

(Reporting by Lisandra Paraguassu; Writing by Stephen Eisenhammer; Editing by Paulo Prada and Daniel Flynn)