Justin Bieber was not listed as the father on the birth certificate of the baby he allegedly fathered with a fan.
Mariah Yeater put her name under the section marked 'mother' but left blank the part of the form where the father's details should have been.
Four months on, she has now claimed the child belongs to the 17-year-old pop singer and has filed a lawsuit demanding a DNA test and financial support.
The disclosure came after it emerged that Miss Yeater, 20, is receiving death threats from obsessed Bieber fans, known as 'Beliebers'.
One message posted by a fan on Twitter said: 'Dear Mariah Yeater, Roses are red, violets are blue, stay away from Bieber or Beliebers will kill you.'