About 200 protesters, well below initial estimates, rallied in front of the Chinese consular office in Manila. Both Beijing and Taiwan had warned their nationals to stay indoors.
The demonstrators, carrying placards and banners and waving Philippine flags, protested against what they called Chinese intrusions into Philippine territory. The one-hour protest ended peacefully under the close watch of dozens of baton-wielding police.
"Encouraging the public to march and protest was a mistaken step by the Philippine side that has made the current situation more complicated and escalated it," Chinese foreign ministry spokesman Hong Lei said.
Government not involved
A spokesman for Philippine President Benigno Aquino denied government involvement in the protest although some of the organizers have links with the president's political allies, including his chief political adviser.
"It was the decision taken by private citizens who feel out of patriotism that they have to speak on the issue. Again, our constitution clearly protects freedom of expression and the right to peaceful assembly," Edwin Lacierda told a press briefing on Friday.
The row over the East Sea is potentially the biggest flashpoint for confrontation in Asia, and tensions have risen since the United States adopted a policy last year to reinforce its influence in the region.
The Philippines is one of Washington's closest allies in the region. The East Sea islands, believed to be rich in oil and other resources, are claimed wholly or in part by China, the Philippines, Taiwan, Vietnam, Malaysia and Brunei.
The Liberation Army Daily, the chief mouthpiece of China's military, criticized the United States' involvement.
"The United States' shift in strategic focus to the east and its entry into the East Sea issue has provided the Philippines with room for strategic manoeuvre, and to a certain extent increased the Philippines' chips to play against us, emboldening them to take a risky course," it said.
Many Chinese, including military officers, have said popular anger could grow if Beijing remains too soft in responding to rival claims in the East Sea. A hard approach to the dispute could underline a message of patriotic unity while serving as an antidote to domestic problems.
The Shanghai government-run website, eastday.com, published a photograph on Thursday that it said showed a reporter from a local TV station planting the Chinese flag on the main reef of the Huangyan island, the Chinese name of Scarborough shoal, where the Philippine coast guard and Chinese civilian ships are engaged in a more than month-long staring match.
Besides Manila, organizers planned protests at China's embassies and consulates in the United States, Canada, Australia, Italy and other Asian capitals. No one showed up to a scheduled protest in Sydney.
Filipinos chant anti-China slogans as they march towards the Chinese consulate in Manila's Makati financial district May 11, 2012 (Photo: Reuters)