Authorities are searching for a letter writer who has targeted more than 40 girls in the Phoenix metropolitan area in the past decade by sending sexually explicit letters to their homes.

Authorities say there are 80 such cases around the county with 41 reported in Arizona, including 29 in Phoenix and Scottsdale.

Phoenix police say the letter writer targets girls as young as 8, tracking them by name and neighborhood through media reports.

The first known victim was a 12-year-old girl in Tucson while the most recent letter was reported in July.

A couple told MyFoxPhoenix their 8-year-old daughter received a letter last fall.

"The letter was downright threatening. Someone says they want to do certain things to your child and they're very graphic, the kind of language he used. Husbands and wives don't talk like that usually," the Arizona couple, who didn't want to be identified, told the station. "It used to be fun to go check the mail with the kids. Now I check the mail, I carry the mail, they aren't allowed to go through anything."

The letter writer has never made any known physical contact with victims and detectives say efforts to identify the suspect through collected DNA have proven futile.

Police in California, Florida, Georgia, Kansas, New Jersey, New York, South Carolina and Texas have also been notified of reported victims.

The Associated Press contributed to this report.

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