BEIJING -- Two Chinese men have been detained for stopping the car of Japanese ambassador and pulling a Japanese flag off the vehicle in downtown Beijing last week, police said Tuesday.

The two men, surnamed Guo and Xia respectively, were detained by police on August 29 in the city of Cangzhou in north China's Hebei Province, according to the Beijing Municipal Public Security Bureau.

Guo, 23 from Hebei, and Xia, 25 from Heilongjiang, admitted they committed the offenses on August 27.

Police said they detained the two men according to China's law on public security administration.

Another man surnamed Liu was issued a warning for blocking the car, police said.

The Chinese government always conscientiously fulfills the Vienna Convention on Diplomatic Relations to protect the safety of foreign embassies and personnel, the Chinese Foreign Ministry Spokesperson's office announced immediately after the incident took place on August 27.