• A fragment of the pilot's life-saving equipment was also found
  • The F-15 fighter vanished from air traffic control radars Monday 
  • The jet did not send an emergency signal before it went missing

Two days after a Japanese F-15 fighter plane vanished from the radar shortly after takeoff over the Sea of Japan, Tokyo has announced that the jet is believed to have crashed. Japan's defense ministry said two crew members are still missing.

The Japan Air Self-Defense Force (ASDF) jet disappeared from air traffic control radars Monday after it took off from Komatsu Airbase, reported The Japan News.

The ASDF and the coast guard found a section of the aircraft body and a fragment of the pilot's life-saving equipment during search operations.

"As part of the fuselage of the fighter jet was discovered in the area, the fighter jet is believed to have crashed," top government spokesman Hirokazu Matsuno told reporters Tuesday.

Two crew members of the aircraft remain unaccounted for. Defense Minister Nobuo Kishi has dismissed reports that one of the pilots had been found. There is no report of damage to fishing boats, the ministry added.

The F-15 jet belongs to the Komatsu base's tactical fighter training group, also known as the aggressor unit. The unit employs elite pilots and plays the enemy role in training for ASDF units across Japan.

The fighter jet did not send an emergency signal before it went missing, Japanese public service broadcaster NHK reported, quoted some officials. The officials believe flight conditions deteriorated so rapidly that the two-person crew didn't have time to respond as they received no calls reporting irregularities or rescue signals from the F-15.

Just after the jet went missing, a top ASDF official was instructed to ensure that all aircraft were thoroughly inspected before and after all flights.

"We are not planning to suspend any (F-15) flight as it was a single accident on the way to training," Kishi said in a press conference. He was responding to the demand from local authorities to halt training until the jets are deemed safe.

F-15s are Japan's mainstay front-line fighter for four decades and are often used to respond when Chinese and Russian aircraft breach the country's buffer zone. Japan has over 200 F-15s, half of which will be soon upgraded to extend their operating life and improve capability.

This isn't the first time an F-15 jet has crashed. An F-15 aircraft belonging to Naha Air Base had crashed in 2011 at Okinawa Prefecture in southern Japan during a training flight above the East China Sea. The pilot died in the accident.

f-15 fighter jet
Representation. A F-15 fighter jet. Reuters