Thousands of anti-Japanese demonstrators mounted protests in cities across China on Sunday over disputed islands in the East China Sea, a day after an attempt to storm Tokyo's embassy in the capital.
Beijing was infuriated last week when Japan said it had bought the rocky outcrops and while the authorities often suppress demonstrations, many of Sunday's events took place with police escorting marchers, while state-run media called the protests "reasonable".
Still, there were reports of violence. Demonstrators in the southern city of Shenzhen -- some holding a banner calling for a "bloodbath" in Tokyo -- clashed with riot police, who fired tear gas to disperse the crowd, Hong Kong broadcaster Cable TV showed.
It also showed footage of more than 1,000 protesters burning Japanese flags in the nearby southern city of Guangzhou and storming a hotel next to the Japanese consulate. Chinese state media reported a turnout of more than 10,000.
Japan's Prime Minister Yoshihiko Noda called on China to ensure the safety of Japanese citizens and businesses after widespread protests on Saturday saw attacks on individuals, establishments and Japanese-built cars.
"This situation is a great disappointment and so we are protesting" to China, he told Fuji Television.
The relationship between China and Japan, the world's second and third largest economies, is often strained by their historical rivalry even though they have significant business links.
The row over the islands, which Tokyo administers and calls Senkaku while Beijing claims them and knows them as Diaoyu, has heightened in recent weeks.
Six Chinese ships sailed into waters around the disputed archipelago Friday, with Beijing saying they were there for "law enforcement", prompting Tokyo to summon the Chinese ambassador to protest what it called a territorial incursion.
Pictures posted on Sina Weibo, China's version of Twitter, showed marches in half a dozen cities around the country on Sunday.
In Beijing, thousands of protesters gathered outside the Japanese embassy, carrying posters of Mao Zedong and Japanese flags scrawled with obscenities, throwing beer bottles and singing the national anthem.
But large numbers of police escorted the protesters as they marched past the building, while volunteers wearing red armbands gave food and water to demonstrators and a medical team stood by.
In Shanghai, where there were major protests on Saturday, more than 1,000 demonstrators gathered outside the Japanese consulate, one group chanting "Down with little Japan."
Police in the commercial hub blocked off roads using shipping containers and plastic barriers, but guided marchers through police lines to protest in front of the building.
One Weibo user in the southeastern city of Quanzhou contacted by AFP said: "There's no violence, just peaceful marches under police guidance."
Hundreds of protesters also marched to the Japanese consulate in the former British colony of Hong Kong, chanting pro-China slogans.
Microbloggers questioned whether Sunday's demonstrations were spontaneous.
"Such large-scale uniform banners and dresses cannot be made in one day. Do you really believe it's people-initiated?" wrote a Weibo user named Linglingqi.
Another user named Afraxafra said: "I feel such a massive demonstration definitely cannot be organised by a small number of average people."
A commentary from the Xinhua-state news agency called the weekend protests "a reasonable move and natural reaction" to Japanese "provocation" and urged Tokyo to take notice, even as it warned protesters against damaging property.
China National Radio said 1,000 Chinese fishing boats were preparing to head to the disputed waters this week after the fishing season in the area resumed.
Another flashpoint could be Tuesday's anniversary of the 1931 "Mukden incident" that led to Japan's invasion of Manchuria, which is commemorated every year in China.
Willy Lam, a China expert at the Chinese University of Hong Kong, said that while the protests may have been encouraged and could continue through Tuesday, the authorities should be able to rein them in soon afterward.
Already they seem to have made greater effort to contain the protests on Sunday than the day before, he said.
"In the beginning the leadership wants to use the so-called public opinion card to put pressure on Japan," he said, adding that they had sufficient manpower to quell protests as needed.