Suspects were apprehended inside their vehicle in Tochigi City on March 26
TokyoReporter
'The cause of death is under investigation,' police said
Prosecution had sought a 10-year prison term
Suspect denies the allegations, telling police, 'I don't know anything'
Canine followed the scent of the suspect to his residence where officers apprehended him
Ordinance is a 500-pound incendiary bomb that was dropped by the U.S. military during World War II
Incident took place during an argument, police said
Suspect is believed to have targeted multiple other women in separate incidents over the past seven years, police said
Population in the town of Wakuya has been on the decline
Suspect allegedly used a knife to slash the neck of his wife, police said