Las Vegas Metropolitan Police have issued a warrant for a DNA sample to see if it matches DNA found on a dress, the Wall Street Journal reported Thursday, citing a law enforcement source.
A spokesperson for LVMPD said the department has submitted an official request to Italian authorities, but that no other detail would be released because the investigation is ongoing.
"The LVMPD is taking the same steps in this case as in any other sexual assault to facilitate the collection of DNA evidence," Officer Laura Meltzer said in an emailed statement.
TMZ has also reported that police met with Ronaldo in the past week and asked for a DNA sample, and that he plans on fully cooperating.
Kathryn Mayorga filed a civil lawsuit last year in Nevada claiming Ronaldo raped her in his Las Vegas hotel room in 2009.
Las Vegas Metropolitan Police also reopened an investigation at her request.
Ronaldo, who plays for Juventus and Portugal's national team, has denied the allegations.
The Associated Press contributed to this report.