MISSOULA, Mont. -

Workers' compensation lawyer Leslae Dalpiaz doesn't work with sex offenders. She doesn't practice criminal law. So when she heard several registered sexual and violent offenders had received letters of warning -- bearing her name and contact information -- she was shocked.

"I am not sending these letters," Dalpiaz said. "I don't mean any ill will to the recipients."

The letters list Dalpiaz as heading Montanans for Family Safety and Women for Justice. Neither group seems to exist.

"During the next twelve months, you may be followed, photographed or otherwise checked for compliance with your sentence..." the letters read. "Considering your record, you have no one to blame but yourself for your deviant behavior."

Dalpiaz says she has no known enemies and doesn't belong to any controversial groups.

"I can't imagine who would want to do something like this," she said.

Dalpiaz is working with police to find out who's sending the letters. She says the fact that the writer included her home address and phone number, as well as her work address, makes them believes she's not a random victim.

"They think it's a personal vendetta," she said. "And that's maybe what scares me the most ... I cannot imagine why someone would want to do this to me."

Some experts on sex offender rehabilitation say it's not unheard of for people -- perhaps fed up with the justice system's approach -- to target those listed in the online public registry.

"It was somebody's idea on how to shake up a system that they probably think is broken. And I understand that," said the University of Montana's Dr. Timothy Conley. "I think for those who would like to see harsher, longer, ongoing punishment of offenders, they need to work through the legislative system to legislate those changes, rather than take it upon themselves to [use] a vigilante punishment approach."

Dalpiaz says the men who received the letters have little in common -- charges vary, conviction dates range from the 1970s to 2000, and none live in the same neighborhood.

She does say that none are repeat offenders, and all have completed their sentences and served the terms of their probation.

"I feel as sorry for the recipients of these letters as I do for myself," she said. "They are targeted randomly, as best we can tell. They are victims, just as I am, of this cruel stalking hoax."

Dalpiaz says she suspects there are more letters out there. She worries someone could receive one, and lash out at her before she has a chance to explain that she didn't write it.

Anyone who has any information is asked to call Missoula Police at (406) 552-6300.

The person who sent the messages could be accused of a criminal act. Delpiaz says mail fraud or stalking charges are possible. And according to the Montana Department of Justice, anyone who uses the online sex offender registry "to injure, harass or commit a criminal act against any person may be subject to criminal prosecution."