State Councilor Dai Bingguo summoned Uichiro Niwa, Japan’s ambassador in Beijing, early today in Beijing and called for the immediate release of the captain, his crew and the boat, the state-run Xinhua News Agency reported.
“Dai expressed solemnly the Chinese government’s grave concerns and its serious and just position,” Xinhua cited the Foreign Ministry as saying in a statement after the meeting.
If the Japanese let the poacher go without penalty, then Japanese waters are going to become Chinese waters. The word "grave" is pretty strong for the detention of a poacher. "Grave" was a word used in communications with Iraq right before Desert Storm in 1991. I have to wonder if the Chinese know what the word means.