A German man arrested over the death of a four-year-old migrant boy has confessed to killing another child, prosecutors said.
The suspect, named as Silvio S, was apprehended on Thursday over the abduction of four-year-old Bosnian Mohamed Januzi on October 1.
The 32-year-old has also confessed to kidnapping six-year-old Elias Sturm in July from a playground in Potsdam, near Berlin, prosecutor Michael von Hagen told reporters.
The suspect told authorities he killed Mohamed a day after abducting him from the capital's central registration centre for migrants, the Berlin prosecutor said.
After sexually assaulting the boy in an apartment in his parents' house in the state of Brandenburg, outside Berlin, the suspect said he strangled Mohamed with a belt "to prevent the noise of his screams", Mr von Hagen said.
In his confession, he told authorities he killed Elias after abducting him from near his parents' home, and buried him in a complex of garden homes in Brandenburg, Potsdam prosecutor Heinrich Junker said.
Police are searching the area for the body, Mr Junker said.
The suspect, who worked for a Brandenburg private security company, was arrested on Thursday at his family's house in Brandenburg after he was reported to police by his mother.
Mr von Hagen said he immediately confessed to killing Mohamed and police found a boy's body in the boot of his car.
The suspect had apparently kept the body in a tub in an upper floor of the house and covered it with cat litter, then moved the tub to the boot of his car early on Thursday.
"Then he drove around for what he claimed was the mundane reason that he wanted to buy a present for his cousin, who as far as I can recall had a birthday, and when he returned to his parents' house the police were waiting for him," Mr von Hagen said.