Matthew Feldman, 24, of South Hackensack told the Star-Ledger of Newark he had believed his mother, Debra, who had longterm drug problems, was in a witness protection program. But he was told recently Debra Feldman, last seen in April 2009, disappeared around the time Keyes is believed to have kidnapped and killed a woman on the East Coast, burying her body in New York, the Star-Ledger reported Wednesday.
Keyes killed himself in December 2012 in the Anchorage, Alaska, jail. He had been charged there with kidnapping and killing Samantha Koenig, 18, a barista at an Anchorage coffee shop.
Before his death, Keyes made some admissions to investigators. The FBI said he likely killed at least 11 people across the country, usually choosing people who might not be missed quickly.
Feldman last saw his mother five years ago. He said he reluctantly gave her money she said she needed to pay her rent.
"It's unfair to say that I didn't care whether she lived or died, but it was once the truth," he told the newspaper. "The last thing I said to her was, 'If you're not going to get clean, you have no room in my life.'"