Police in the Guangdong provincial capital have detained 10 people suspected of involvement in vandalism and looting while protesting Japan's moves to nationalize China's Diaoyu Islands.

According to a press release issued by the Guangzhou city public security bureau on Sept 17, police in the city's Tianhe district detained seven suspects on Sunday afternoon.

Police believe the suspects destroyed and damaged Japanese cars during a protest against Japan's illegal purchase of the islands.

Meanwhile police detained another three suspects who allegedly broke store windows and billboards during the protest.

The suspects have been detained for administrative detention, said the press release.

Police urged people to abide by the law while expressing their patriotism.

Thousands of residents rallied on Sept 16 in Huanshi Road where the Japanese Consulate General in Guangzhou is located.

A large number of Japanese vehicles were destroyed and damaged when a handful of protesters threw water bottles and stones at the cars.

Traffic in the busy Huanshi Road and Tianhe district, a financial center in Guangzhou, came to a standstill.

"I hope the protesters will not be used by a handful of people who have ulterior motives," said Chen Wangzhong, who lives nearby.