Rallies and protests broke out in several Chinese cities on Tuesday to oppose Japan's "purchase" of the Diaoyu Islands and their affiliated islets.

More than 10 protestors gathered at the Japanese Embassy in Beijing on Tuesday morning, holding placards that read, "The Diaoyu Islands are Chinese territory."

Also on Tuesday morning, several people in Guangzhou, capital of south China's Guangdong Province, gathered outside the Japanese consulate, shouting slogans such as, "Protect the Diaoyu Islands!"

About 200 people in Weihai, Shandong Province, began marching on the streets around 10:40 a.m., waving anti-Japanese banners and chanting anti-Japanese slogans such as, "The Diaoyu Islands belong to us!" and, "Boycott Japanese goods!" They dispersed at about 11:30 a.m.

The Japanese government on Tuesday signed a contract with the Kurihara family, who the Japanese side claims to be the "private owner" of the Diaoyu Islands.

The signing of the contract came shortly after the Japanese cabinet decided earlier in the day to use reserve funds to "purchase" part of the islands despite a string of strong warnings and opposition voiced by top Chinese leaders.

On Monday, China's Foreign Ministry promptly challenged Japan's reckless actions in regards to the Diaoyu Islands, with Foreign Ministry spokesman Hong Lei saying China firmly opposes the move.

Meanwhile, Chinese Foreign Minister Yang Jiechi on Monday summoned Japanese Ambassador to China Uichiro Niwa for a meeting to lodge solemn representations and strong protests against the Japanese government's illegal "buying" of the islands.

Yang said the Diaoyu Islands and their affiliated islets have been China's inherent territory since ancient times, which is backed by historical and legal evidence.

The Japanese government's so-called "purchase" of the islands and other unilateral actions are illegal and invalid, Yang said.