LARGO, Md. (WUSA) -- The man suspected of killing at least 4 women, and perhaps more, is slightly built, but "the most intelligent criminal I have ever dealt with," according to one investigator.
The 27-year-old man who is described as a "person of interest" in the cases that became known as the "Mother/Daughter Murders" in Largo lived with his parents in the same home he grew up in until his arrest on unrelated federal gun charges in July of 2009.
His name has not been released by authorities until he is formally charged.
But court records and interviews with law enforcement sources and people who know the suspect paint a picture of a young man who is at times a ruthless criminal and at other times the unassuming neighbor next door.
He is 5'8" tall and weighs a slight 150 lbs.
He was a part-time employee at UPS in Landover Hills and may have had access to customer records, sources say.
He lived within a 2.2 mile radius of his victims in the Largo Mother/Daughter cases.
Karen Lofton and her 16-year-old Karissa were shot in their home by an intruder in January of 2009.
In March 2009, the bodies of Dolores DeWitt and her 20-year-old daughter Ebony were found in a burning stolen car a few blocks from their home.
Neighbors described him as a "brainiac" who skipped at least one grade in elementary school but who was accused of breaking in to one neighbor's house when he was a young teen.
Court documents indicate the man worked with a fellow UPS employee to sell stolen weapons from the trunks of their cars parked at the facility.
In one case last year, the federal government paid an informant a thousand dollars to arrange for the purchase of weapons there.
This "Person of Interest" graduated from Largo High School and went on to earn a degree at the University of Maryland University College, a source close to his family said.
But court records in cases unrelated to the Mother/Daughter murders sketch a much different picture.
He was charged in two fearsome home invasions dating back to October of 2008.
In one case, the suspect and an accomplice, wearing masks at 4:30 a.m., herded an entire family at gunpoint into a room in their home in a botched attempt to steal an Aston-Martin car.
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One victim managed to wrestle a gun away from one intruder and the suspects fled.
In another case that happened within a few days of the DeWitt murders, the suspect and an accomplice is accused of waking up another woman at gunpoint to steal her 2002 Cadillac, bank cards, and a handgun.
Many of the past charges against the suspect have been dropped as prosecutors re-align their efforts to target the him in the murder cases.
The "person of interest" was arrested in a stolen-gun purchasing sting set up by the federal Bureau of Alcohol Tobacco and Firearms in July of 2009.
In that case, the suspect is accused of selling weapons, including assault-style rifles and handguns with silencers, to undercover agents after an informant tipped off investigators.
Some of the guns were stolen in a gun store burglary in Woodbine, Md.
The gun sting occured in the parking lot of the Landover Hills UPS facility where sources say the suspect worked part time sorting packages.
In addition to the Largo Mother/Daughter murders, the person of interest is a suspect in the home invasion murder of a woman in Bowie where a fire was set.
Prince George's County Police Chief Roberto Hylton has predicted that the suspect will eventually be linked to other murders "beyond the boundaries of the county and perhaps in other states."
In the meantime, prosecutors are working with a county Grand Jury to secure indictments in the murder cases. Formal charges are expected to be filed early next week.
Written by Scott Broom
9NEWS NOW & wusa9.com