An Indian-origin man on Tuesday was charged with the murder of his one-year-old son and the attempted murder of the toddler's twin sister, the media reported.
Bidhya Sagar Das, 33, was arrested on Sunday following a dramatic 20-hour manhunt after the two children were discovered with critical injuries at a flat in Finsbury Park, north London, on Saturday, reported the Daily Mail.
Reports said the two children had been battered with a hammer.
The twins, Gabriel and Maria, were rushed to hospital where the boy died on Sunday while the girl remains critically injured, said the police.
Das has been charged with the brutal attack and was due to appear in custody at Thames Magistrates' Court.
The boy's post-mortem examination was due to take place at a central London hospital.
Detectives from the Homicide and Major Crime Command, led by detective chief inspector Dave Whellams, continue to investigate the case.
"This is clearly a tragic incident, and our thoughts are with the family of the two young children," Whellams said.
Neighbours said that the twins lived on the top floor of the building with their Romanian mother, Cristinela Datcu, and Indian-origin father.
It is believed the mother was locked in the bathroom as the children were attacked with a hammer, the Mail reported.
Das worked as a receptionist at a nearby hotel, but quit his job two days ago.