A police officer in Japan has been arrested after he was suspected of killing his girlfriend in an attempt to conceal their affair.

Takashi Mizuuchi reportedly used a belt to strangle his 23-year-old mistress, Hikaru Shirata in her apartment at Higashisumiyoshi Ward in Japan.

It was revealed that Hikaru Shirata had threatened to end the relationship and inform the wife of Hikaru Shirata of their affair.

According to reports, she was seen in her bathtub at about 11.am fully clothed but lifeless after the apartment building manager received a report from her workplace that she had not showed up for work and that they could not contact her.

Takashi Mizuuchi was arrested on Sunday, January 25 and confessed to the police that he strangled the deceased in order to prevent her plans to disclose the secret of their love affair to his wife after ending the relationship.

Takashi Mizuuchi who got married last August has been charged to court with murder.