The FBI this week came down hard on a Chicago man they say has been cyberstalking an L.A.-based model the Weekly has determined is Kourtney E. Reppert.

An FBI affidavit in the case against 47-year-old Luis F. Plascencia identifies the victim as “K.E.R.,” indicates she's originally from “Philly,” and says she's affiliated with a website called Bombshell Marketing, all of which led to Reppert.

Plascencia, a winner who lived with his mom, allegedly cyberstalked her this spring and sent her hateful, venemous messages via Facebook and from several different email addresses, according to the FBI's allegations:

According to the affidavit Plascencia posted personal information about Reppert (he had her family's home address) and threatened to “cut your fucking head off,” “kill your parents” and cut her family “to pieces” if she didn't stop modeling.

Credit: Kourtney Reppert / Facebook

Credit: Kourtney Reppert / Facebook

The messages were sent via Facebook and email, according to the agency.

Plascencia was upset that she was engaged in semi-nude, lingerie and bikini modeling although, at one point, he posed as someone else and asked Reppert to model nude for him, according to the allegations. In another instance he allegedly wrote:

I'm going to stab you in the fuckin' heart and cut your head off.

At various times he called her a “slut,” “whore” and “gutless bitch” in messages to Reppert, the FBI says, and he even criticized her looks, saying she was a “fat ass.”

Credit: Kourtney Reppert / Facebook

Credit: Kourtney Reppert / Facebook

He once allegedly indicated when and where Reppert would celebrate a friend's birthday. And Plascencia told her that he talked to Reppert's friends, agents said.

Agents allege the suspect even sent her a CD-ROM of 234 online photographs of her that he had collected.

At one point Reppert hired private security guards to accompany her to public events, the FBI says.

After she hired a private investigator who appeared to track down the suspect, Plascencia allegedly sent her emails saying he would stop, apologized profusely, and then deleted his core internet service and email accounts, the FBI says.

Several email addresses and IP addresses were used in the communication, but agents ultimately tracked Plascencia down to the Chicago apartment he shared with his mom and sister, according to the affidavit.

Agents say that Plascencia admitted he asked a neighbor to scrub his hard-drive and that he admitted to using Chicago public library terminals sometimes (agents tracked IP addresses in the case to the library and to his Comcast account, they said.).

They also said a search of his apartment turned up several CDs of photographs of Reppert, one of which was set to music.

He was arrested Tuesday at the residence at 5421 North Lovejoy in Chicago, according to the agency.

Plascencia was charged in U.S. District Court in Los Angeles this week with interstate stalking and faces up to five years behind bars if he's convicted. He's due in court Friday.

On her website, Reppert says she's only been in L.A. about year but already has representation from a top modeling agency and shows in the works for CBS and Fox.

Late last night Reppert tweeted that she was disappointed the L.A. media had figured out who she was, saying that “the cat's out of the bag” (in a message she soon deleted), and stating:

[@dennisjromero / / @LAWeeklyNews]

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