French Gendarmes walk past a banner for the forthcoming Paris 2024 Olympic Games. GETTY IMAGES

French authorities are preparing to combat a wave of scams targeting the millions of visitors expected during this summer's Olympic Games and Paralympics, they have said.

Processed food advertised as "homemade breakfast", fake stars added to hotel ratings, or a failure to post room prices are among the traps anti-fraud police expect to be laid for unsuspecting visitors. For now, authorities are calling such incidents minor, still mostly limited to the hotel sector, according to the finance ministry's consumer protection unit.

But it will not stay that way, the unit warned, saying that checks on businesses would "intensify before and during the Olympic Games" to ensure that information given to consumers was accurate, "and products sold are not counterfeit or dangerous", unit director Sarah Lacoche told reporters.

More than 4,000 checks of businesses had already been carried out and 6,000 more were to come, all specifically targeted at preventing Olympics-related false advertising and scams, including fake Games merchandise.

Probes carried out by a total of 2,900 anti-fraud agents would include sophisticated detection methods such as X-rays of suspicious products. "We have started to identify a few small problems," Lacoche said.

These included fictional airport transfer services, or the deletion of negative customer reviews from hospitality websites, she said. The unit encouraged people to use a dedicated app, SignalConso, which would have an English-speaking version for foreign visitors, to denounce scams.