All 14 people who sailed to the Diaoyu Islands were sent home by the Japanese authorities without being prosecuted yesterday.
They headed back to Hong Kong in two batches of seven, the first arriving by air at 8pm and the second setting sail in the fishing boat that took them to the islands on Wednesday.
Escorted by a Chinese vessel, they are expected home early next week.
The returning voyagers were greeted in the arrival hall of the airport last night by more than 100 people including their families and members of the Action Committee for Defending the Diaoyu Islands.
No senior government officials were seen. "We won't let go of a single bit of our territory. Down with Japanese militarism!" the group shouted, still spirited after 16 hours of detention and a two-hour flight.
But they weren't hailing the voyage as a success. "This is not a real victory," activist Koo Sze-yiu said.
"Japan is still occupying the Diaoyus. It is the Chinese government that has brought national humiliation by letting go of our territory, while maintaining suppressive rule over the ordinary people."
Another activist, Tsang Kin-shing, better known as "The Bull", echoed: "I didn't see the central government offer much assistance. The whole process was a people's initiative."
The activists also said they refused to sign documents provided by the Japanese that would make them admit illegal entry.
Foreign Ministry spokesman Qin Gang said last night that the detention of the activists by Japan was a "gross violation of China's territorial integrity". He also issued a "serious protest" about the interception of the Hong Kong activists' boat.
Qin said China had long advocated the settling of the dispute through dialogue and demanded that Japan stopped taking action that intruded on China's territorial integrity in the interests of maintaining positive Sino-Japan ties.
Recalling the approach to the islands, the activists said nine Japanese vessels intercepted their trawler, The Kai Fung No2, when it was 15 nautical miles from the Diaoyus. "Surprisingly, the vessels left when we were five nautical miles away," Tsang said. Design teacher Lo Chung-cheong said vessel owner Lo Chau threw batteries at the Japanese boats, adding: "We all swore and threw bricks at them.
"It was very intense ... I believe the Japanese were scared of us."
Later however the fishing boat was sandwiched between two Japanese ships a few metres from one of the islands, at which point seven activists leapt out and swam ashore.
Jiang Xiaofeng, of Phoenix TV, one of those who returned yesterday, urged the Japanese government to return his recordings of the journey, which were confiscated.
The crew left the city on Sunday for the uninhabited islands, claimed by China, Taiwan and Japan, which calls them the Senkakus.
The seven members who returned by air were taken to Naha Airport where they boarded a Hong Kong Airlines flight at 5.15pm yesterday. The other seven were taken to Okinawa's Ishigaki port to recover their vessel and were supplied with food and fuel before being escorted out of port by two coastguard vessels.
The Hong Kong government said Beijing would send a vessel to escort the trawler home. The spokesman said the government was "grateful" to the central government for lodging solemn representations with the Japanese government.
The decision to deport, rather than prosecute, the 14 activists was made at a special meeting of the Japanese cabinet. Prime Minister Yoshihiko Noda told his ministers: "It is really regrettable that they entered Japan's territorial waters and illegally landed on Uotsurijima, despite our repeated warnings." Uotsurijima is called Diaoyu by China.
Japan's Chief Cabinet Secretary Osamu Fujimura later said Japan's coastguard concluded that the group's acts did not obstruct the duties of law enforcement officers, although they threw bricks at a Japanese patrol ship and injured no one. The decision was "based on domestic law and not on emotion", he added.
Li Nan, a member of the China Federation of Defending Diaoyu Islands, said : "Japan should not think the whole saga has ended just because the activists have returned home. The Chinese government should also give an explanation to the public on why Japan can illegally detain our citizens."
Additional reporting by Laura Zhou