Police in Vietnam allowed up to 300 peaceful anti-Chinese protesters to march in central Hanoi on Sunday after their suppression of earlier rallies sparked anger on the Internet. It was the eighth consecutive Sunday that protesters have gathered over tensions in the South China Sea. Authorities tolerated the first five small protests near the Chinese embassy, but then forcibly dispersed two demonstrations and briefly detained people after talks between Hanoi and Beijing in June. Sunday\'s protest took place at a different location -- around Hoan Kiem lake which is a popular meeting place for Hanoi residents and foreign tourists. \"I want to send a message to China that they stop doing bad things with our country,\" said Nguyen Quang Thach, 36, who attended all the rallies. Overtly political demonstrations are rare in Vietnam, despite fairly frequent protests in the form of land-rights rallies and strikes by factory workers. Some demonstrators wore T-shirts objecting to China\'s maritime claim to essentially all of the South China Sea, called the \"East Sea\" in Vietnam. Vietnam and China have a longstanding dispute over sovereignty of the potentially oil-rich Paracel and Spratly island groups, which straddle vital commercial shipping lanes in the South China Sea. Tensions flared in May when Vietnam said Chinese marine surveillance vessels cut the exploration cables of an oil survey ship inside the country\'s exclusive economic zone. Vietnamese bitterly recall 1,000 years of Chinese occupation and, more recently, a 1979 border war. More than 70 Vietnamese sailors were killed in 1988 when the two sides battled off the Spratlys. Protesters chanted that the Paracels and Spratlys belong to Vietnam, and carried signs with the names of military personnel who died in previous clashes with Vietnam\'s giant neighbour. At least one man held a picture which allegedly showed a policeman stomping on a demonstrator when officers broke up a similar rally a week earlier. Video of the alleged incident was posted on the Internet, where independent blogs and opinion flourishes despite the arrests of some bloggers. All official media are state controlled. \"Beating patriots whose only crime is expressing their patriotism against foreign invasion must be seriously and publicly punished,\" Nguyen Ngoc, a writer, said on the Nguyen Xuan Dien blog, which has become a rallying point for the protesters, many of whom are respected senior intellectuals.