TOKYO — A Japanese defense helicopter carrying four crew members lost contact during flight training in central Japan on Tuesday evening and is feared to have crashed.

The UH-60J disappeared from radar while flying over the Pacific Ocean about 18 miles south of Hamamatsu, a coastal city in central Japan, defense officials said.

Defense Minister Itsunori Onodera told reporters that rescuers dispatched to the site spotted objects that appeared to be broken parts of the helicopter floating in the water, suggesting a crash.

The helicopter belongs to the Japan Air Self-Defense Force base in Hamamatsu, about 150 miles southwest of Tokyo.

It was on a nighttime search-and-rescue flight training mission and lost contact soon after taking off from the base, Kyodo News service reported.

In August, another defense helicopter, an SH-60J, crashed off the northern Japanese coast, leaving three of its four crew members missing.