A Mexican father who claimed he gave away his two children to cancel a debt has admitted killing them, police say.
Javier Covarrubias initially said the two toddlers had been kidnapped, but changed his story when confronted with evidence that his account was false.
He now says he asphyxiated the children and hid their bodies in different locations in Mexico City.
Police have found two bodies wrapped in plastic bags and DNA tests were being conducted to confirm their identities.
Mr Covarrubias, 20, did not say why he killed one-year-old Isis and two-year-old Darien, prosecutors said.
His initial claim that they had been snatched from him in a street attack in the poor Mexico City neighbourhood of Tepito on 18 May provoked angry protests by residents demanding better security.
But when police confronted him with video evidence showing he had not been in the area at the time, he changed his story, saying he had given the children away to a Mexico City woman to cancel a 25,000 peso (£1,300; $1,900) debt.
Now he has admitted that he murdered them in a park where he had taken them for a walk, prosecutors say.
Mr Covarrubias was arrested in Hidalgo state after going into hiding when police questioned his initial account of his children's disappearance.