With one month to go before the Paris Olympics, security has become a major challenge for the French capital.

About 10,000 athletes will parade for six kilometers on the River Seine aboard roughly 90 boats at the opening ceremony. More than 320,000 spectators are expected to line the riverbanks to see the parade.

Games organizers say this is the first time the opening ceremony of Summer Olympics will be held outside a sports venue.

To prevent terrorist attacks, Paris authorities plan to create security zones around the river from July 18, eight days before the ceremony.

Only spectators and Games-related officials will be allowed to enter the areas. People who live or work in the areas can apply for a pass on a special website and obtain a QR code, which they need to present to enter.

Authorities plan to mobilize 45,000 police and other security personnel on the day of the ceremony.

France raised its terror alert level to the highest nationwide in March. Police arrested a man from Chechnya, southern Russia, on suspicion of plotting an attack at an Olympic venue in central France in May.

Paris police chief Laurent Nunez told reporters on Friday that terrorism by Islamic extremists is a main concern.

Meanwhile, restaurants and other businesses in the designated areas are concerned that tight security could affect their operations.

A restaurant along the Seine, which has 200 seats including those on the terrace, says it has not decided whether to stay open during the Games, because customers need to apply for a pass and it remains unclear whether food will be delivered as usual.

Some local businesses are said to have decided to close down during the Games and are considering seeking compensation from local authorities.

The manager of the restaurant said the staff initially expected the Olympics to be a business opportunity, but the event will instead cause a great loss.

The manager also says authorities need to strike a balance between providing security and keeping restaurants and bars open.

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