TOKYO, Sept. 7 (UPI) -- Japan and China exchanged protests after collisions between vessels off the Japanese-controlled Senkaku Islands Tuesday, officials said.

The collisions between two Japanese patrol boats and a Chinese fishing boat occurred in the East China Sea, the Kyodo News service reported.

The Chinese fishing boat's bow hit the Japanese patrol boat's stern at around 10:15 a.m., the report said. The Chinese trawler also was operating in Japanese territorial waters when it collided with a second Japanese patrol boat about 40 minutes later, the Japanese coast guard said.