Nine people, including four high school students, were reported missing Friday after a Japanese training ship sank following a collision with a U.S. nuclear-powered submarine in waters off Hawaii, the Japan Coast Guard said Saturday.

The 499-ton Ehime Maru, from Uwajima Fisheries High School in Ehime Prefecture, had 35 people on board when it collided with the 6,080-ton attack submarine USS Greene- ville in the Pacific some 18 km south of Oahu Island at around 1:45 p.m. local time, the Japan Coast Guard said.

The missing students have been named as Toshiya Sakashima, Yusuke Terata, Katsuya Nomoto, Takeshi Mizuguchi, all 17 years old, instructors Hiroshi Makizawa, 37, and Jun Nakata, 33, chief engineer Toshimichi Furuya, 47, engineer Hiroshi Nishida, 49, and chief radio operator Hirotaka Segawa, 60.