Hyogo prefectural police said investigators found a torso, arms and legs in three locations in parts of Kyoto and Osaka on Sunday.
He later admitted to disposing of the missing woman's body, police say.
Police have formally arrested the 26-year-old and he has confessed to "abandoning the woman's body", according to national broadcaster NHK.
The decapitated head was found over the weekend as police searched the apartment for signs of a missing 27-year-old woman who vanished after telling a pal she was meeting an American tourist she found online, The Ashashi Shimbun reported.
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Eastburn said the Pentagon expects Trump's policy announcement on transgender service members "no later than March 23". McMaster would also have the option of retiring from active duty at any time if he chose to do so.
Video records from security cameras and other devices showed that Bayraktar went in and out of the Higashinari condominium several times carrying a large travel bag on February 18.
The American was arrested on February 22 for "confining" a missing 27-year-old woman, from Sanda in the Hyogo Prefecture of Japan, who had been missing since February 16, in the apartment he was staying in.
Two days later the woman's head was found in a suitcase at a different short-term rental property in Osaka.
A large amount of air-freshener had been used in the condo and part of the woman's driving licence was found there also, sources said.
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The president said unless a school has "offensive capability, you're wasting your time, you're wasting your time". They've mounted an all-out campaign to win stricter gun law, leading their peers across the U.S.
A man believed to be Bayraktar and a woman were seen on surveillance footage going into the Osaka apartment building together. But she was never seen in subsequent footage, the Kyodo News agency reported, citing unnamed investigative sources.
The suspect, who arrived in Japan in January, was arrested Thursday on charges of confining the woman against her will. The site and others reported that the American had denied any knowledge of what happened to the woman, whose name was not released.
Hyogo Prefecture police, where the unnamed missing woman is from, declined to answer questions Monday night.
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Mr Gee's remarks come after a stronger condemnation from another Nationals MP, who openly called on Mr Joyce to quit. Joyce said at the news conference.