A German security official with knowledge of the case, speaking on condition of anonymity, confirmed the name. Dutch police spokeswoman Chantal Westerhoff said he was "a 20-year-old man from Hengelo" - near the German border.
When confronted with the facts, police say, van Helsum admitted the truth.
"The young man known as 'Ray' was confronted with the results of the investigation," police said in a statement. "He then confirmed his real personal details and admitted that the previous story - that he had lived for years in the woods - had been invented."
A Dutch website on missing relatives carried an entry on Robin van Helsum, saying he was born in 1992 and had been missing since Sept. 2, 2011 - three days before he arrived in Berlin. Robin "left after leaving a farewell note. He was last seen traveling with a friend to Berlin. Since then every trace of him is gone," the entry on Vermist.nl says.
Berlin police said that even though he had been reported missing, there was no active investigation into his disappearance because there was no evidence of foul play and he was an adult.
Van Helsum showed up Sept. 5 at Berlin city hall claiming that his mother had died in a car crash when he was 12 and that he and his father had been living in the forest outside the German capital. He claimed not to know his last name or where he was from and spoke English but little German. He said his father had died in August and he buried him in the woods.
Police are now checking whether van Helsum could be charged with fraud.
The young man's father "was very sick and in fact has since died. He had reported him [Robin] missing," Westerhoff said in the Netherlands.