Is DC-Area Serial Killer Behind Bars, After Targeting Young Women and Their Mothers?

WASHINGTON (CBS) For more than a year the families of Karen Lofton and her daughter Karissa, and Delores Dewitt and her daughter Ebony, have grieved for the loved ones who were brutally taken from them in January and March 2009, respectively, while the cases grew colder by the day.

But now Prince George's County, Md. police believe they have a man in custody who is responsible for all four homicides.

Karen Loften, 45, a nurse, and her daughter Karissa, 16 were found Jan. 26, 2009, shot to death in their locked home sometime around 2:30 a.m. The timeline was established because Karissa reportedly called 911 at 2:30 a.m. and told the operator that she and her mother had been shot, sources told The Washington Post at the time. Police initially thought that the killer must have known the victims because the house was locked when they were discovered and there was no evidence of forced entry.

That all changed on March 15, 2009, when the bodies of Delores Dewitt, 42 - also a nurse - and her 20-year-old daughter, Ebony, were found in a burning car that had been reported stolen earlier that day.

Despite the differences in the cases - the Loftons' murder seemed more planned and no attempt to cover it up was made, the Dewitts' killer may have moved the bodies in an attempt to cover up the crime - Prince George police assigned more than two dozen investigators to the two cases, the Post reported.

Maj. Andrew Ellis, a Prince George's police spokesman, said Monday that "we've identified a person of interest in both cases," but he declined to provide details. He said investigators had turned over the results of their probe to the Prince George's state's attorney's office, the paper reported.

Although Maj. Ellis would not elaborate on who the man is or what evidence they have, sources within the investigation say he is a stranger to the victims with no obvious motive for the killings and that investigators believe they may have a serial killer on their hands. The man seems to be well educated and is being held on unrelated federal charges, sources told The Washington Post.

The families of the victims told the Post that they have not been briefed by the police, but Delores Dewitt's mother told the Post that she is hopeful the new lead will mean closure for her family.

Karissa Lofton's father, however, is taking a more cautious, skeptical approach to the news of a possible break in the case, and hopes the police aren't just trying to use a suspect in one case to close another, he told the Post.

"I don't really feel comfortable with them saying that these two are linked without showing me any evidence why they think this," Kirkland Lofton said Monday.