UPDATE: Thursday - 3/14/2013, 6:59pm ET
WASHINGTON - Manassas City Police have released a sketch of a suspect in the case of threatening letters left at several homes since December.
Police describe the suspect as a male, light brown to black hair, light to medium complexion, medium build, and average height.
Anyone with information about this case is encouraged to call the Crime Solvers' anonymous tip line at 703-330-0330, or to call the Manassas City Police Department Investigative Services Division at 703-257-8092.
The Manassas City Crime Solvers will pay a cash reward up to $1,000 for information that leads to an arrest in these cases.
The confidential 24-hour tip line is 703-330-0330.
EARLIER: Tuesday - 3/12/2013, 11:26am ET
WASHINGTON -- Manassas police will soon release a composite sketch of a man suspected in leaving 18 threatening notes at several homes since December.
"We've only had a couple of folks who have seen somebody suspicious, and we have one recently that we're hoping remembers enough details of what they saw," says Sgt. Lowell Nevill.
Nevill says police hope to release the sketch in a few days, but have not specified when it will be made public.
The police spokesperson says the person has been described as male, between the ages of 20 and 30, with dark hair, although heights range from 5-feet-2 inches to 6 feet.
Police are also providing more detail about the notes, which have been left outside a front door or tucked inside the door frame.
"They're usually a medium-sized white, unlined piece of paper, handwritten notes" says Nevill. "Sometimes blue, black, green, red ink -- sometimes a couple different colors on the same note."
Nevill says all the notes have contained threats to kill.
"There is at some point a word or two such as that, that is threatening. Sometimes there are some expletives in there. It's generally 15-20 words," Nevill says.
The same person -- who is not a public figure -- is named in each letter, but police have not identified him to protect his privacy. Nevill says the man who is singled out has talked with detectives and they are working to determine why he is repeatedly mentioned.
At this point, police have no motive for the threats. Police have recovered fingerprints from the letters,and are working with crime labs.
Nevill is asking for the public's help in reporting people suspiciously approaching homes.
"If they hear their doorbell ring, or hear anybody at the front door, look before they open," says Nevill.
The notes began appearing in December, but stopped for several months, before resuming the week of March 2.
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