China demanded an apology and compensation on Saturday after Japan returned a fishing boat captain who was arrested more than two weeks ago in disputed waters, dpa reported.
"Such an act seriously infringed upon China's territorial sovereignty and violated the human rights of Chinese citizens," China's foreign ministry said in a statement.
"Japan must apologise to China and offer compensation over this incident," it continued.
The fishing boat captain, Zhan Qixiong, arrived in Fuzhou in south-east Fujian Province early Saturday morning via a chartered plane, where he was met by assistant foreign minister, Hu Zhengyue, the official Xinhua news agency reported.
The 41-year-old sailor had been arrested, and 14 crew members detained, after a collision off the coast of a set of islands known as Diaoyu in China, Senkaku in Japan and Tiaoyutai in Taiwan.
The seabed in the surrounding area is thought to be rich in natural gas.
After the arrest on September 7, China had made repeated representations to the Japanese Ambassador calling for Zhan's "immediate and unconditional" release.
On Friday, Japanese Prosecutors decided to halt further investigations into the collision and release Zhan.