The fax also stated that the woman would have been reported missing by her family.
The fax named a suspect in the killing and gave the name of another man who helped clean the car with the suspect.
One of the men named is already in jail being held on another charge not related to this case. He was arrested on March 3 and is in jail in lieu of $150,000.
The sedan found was registered to the dead woman, 22-year-old Denise Figueroa. She had been missing since February 28. An autopsy will be performed on Monday.
Fox News reports that the person last seen with Figueroa had called her father and told him “I didn’t mean to hurt her. I’m sorry, I’m sorry.”