Police have not ruled out that the case is result of foul play
Bodies are likely those of two brothers, aged in their 70s
Shinjuku Police Station deputy chief said, 'I would like to investigate the cause and circumstances in detail'
Woman was reported missing in July 2021
Woman likely died within the last week, police said
Woman was last seen on June 27, 2021
A survival knife was found at the side of the bed, police said
Regarding the app, he said, 'I wanted to stop, but I couldn't'
Gender of the body is not known
Suspect said, 'I went into a panic'