A 22-year-old man was briefly detained on suspicion of killing his 19-year-old wife by injecting her with liquid nicotine on their honeymoon in Osaka, Japan, Sejong Police Station said Wednesday.

The man is accused of murdering his wife on April 25 last year by injecting her with the prepared substance in order to claim the victim’s life insurance payout, worth 150 million won ($140,000).

The murder suspect reported to dispatched Osaka policemen that his wife had “committed suicide.” 

After consulting with his deceased wife’s family, the man chose to cremate her body and returned to Korea shortly after holding a funeral.

Local police were able to track down the murder suspect after obtaining the victim’s autopsy report from Japan with Interpol’s assistance.

The autopsy revealed that the victim died from a nicotine addiction. Police said they also found the suspect’s detailed planning for the murder in a diary.

The suspect claimed that his wife wanted to kill herself, so he only helped her inject the nicotine. He, however, denied the murder allegation.

Police discovered that the suspect had tried to kill his former girlfriend, 22, with nicotine as the murder weapon two years ago on Dec. 20, but failed to see it through.

The former girlfriend said to police that the nicotine-infused drink her then-boyfriend gave her “tasted weird” and “did not finish the drink.”

By Catherine Chung (cec82@heraldcorp.com)