The Osaka District Court on Monday fined a man ¥300,000 ($2,200) for briefly putting his 2-month-old son in the freezer compartment of a fridge in a hotel guest room in April last year.

Tatsuji Nishioka, 43, who was convicted of assault, admitted he put the boy in the fridge freezer in Fukuoka, but said it was "only for a short duration to take pictures," insisting his actions should not be viewed as a crime.

The court only ordered him to pay a fine, which met the full amount demanded by prosecutors, as it did not acknowledge that the boy suffered health problems afterward.

Judge Yuko Okubo dismissed Nishioka's defense of his actions as "unreasonable," saying that children of such a young age are not capable of regulating body temperature and that his son could have suffered frostbite and hypothermia.

According to the ruling, Nishioka put the boy, his second son, in the freezer in the hotel room in mid-April last year. The prosecutors said the freezer operated at minus 18 degrees Celsius and that the child was wrapped only in a baby blanket.

The boy was temporarily placed in the custody of a child welfare center in September last year. According to the Osaka Prefectural Police, evidence of what appeared to be abuse of the child was found on the father's smartphone and laptop.