Police said Sunday the message was found during the weekend when police were called to a basement apartment where Vindalee Smith, 38, was found stabbed and her throat cut, the New York Post reported Monday.
"The note was underneath the body. They found it when they rolled her over," a law enforcement source said.
The note warned one pregnant woman would die each week unless Lee Boyd Malvo was released from prison, a source familiar with the message said. Malvo, 27, is serving life in prison for six of the 10 sniper attacks in the Washington area in 2002. He and his mentor, John Allen Muhammad, who was executed in 2009, had planned to kill six white people a day for a month.
Investigators said while they believe the note was meant to throw the investigation off-track, they won't rule anything out, the Post said. Sources said police haven't found any connection between Smith and Malvo.
Police believe Smith, whose body was found Saturday, knew her killer, explaining there was no sign of forced entry. Police said a weapon has not been found.
Smith, a mother of four children in their late teens and early 20s, had planned to marry Anthony Jackman Sunday, friends told the Post. Police sources said Jackman, who was questioned by police Sunday, was already married.