Police in Osaka have arrested a 26-year-old unemployed man on suspicion of fatally abusing the one-year-old son of his girlfriend with whom he lived.

The incident occurred at around 4-5 p.m. on Oct 6 at an apartment in Asahi Ward, TV Asahi reported. Police said Rento Hasegawa is accused of punching the child, Yuto Nishimura, in the stomach and pushing him off his chair.

Yuto’s mother was away from home at the time. When she returned at around 12 noon the next day, she noticed that he looked pale and called 119. He was taken to hospital where he later died due to abdominal bleeding from internal organ damage.

Police said Hasegawa has partially denied the charge. He was quoted as saying, “Yuto tipped over his bowl of ramen, so I hit him in the stomach with the palm of my hand and pushed him away. He fell off the chair but I don't think my actions caused his death."