Japanese car rental agencies are warning Chinese tourists who improperly obtain an international driver’s license online that they will not be allowed to rent vehicles, The Okinawa Times reports.

Since China did not sign the 1949 Geneva Convention on Road Traffic, which established international standards for road signs and rules, Chinese citizens who visit Japan, and other countries, cannot use their Chinese driver’s licenses when renting vehicles.

Because of this, several online sites have been created, offering Chinese citizens an international driving permit issued from countries that did sign the 1949 agreement. According to the news source, fraudulent driver’s licenses have largely been coming out of Philippines.

However, Chinese citizens who stay in Geneva Convention member countries can obtain international driving permits, making it difficult for rental agencies to determine which licenses are real, and which are fake.

Japan's National Police Agency is investigating the issue with the All Japan Rent-A-Car Association. The Okinawa Times reports that some Japanese rental companies have refused to rent cars to Chinese customers who have presented international driving permits issued in the Phillipines.

At the same time, Times Car Rental has updated its procedures to check for licenses obtained improperly. 

Related: How Can My Rental Company Prevent Identity and Credit Card Fraud?