NEW YORK (1010 WINS/WCBS 880/AP) — “Law & Order: Criminal Intent” star Kathryn Erbe testified Wednesday that she got a “very bad feeling” from an accused stalker when he approached her on location.

The actress cried when she testified at the federal trial of Charles Nagel of Philadelphia, who has pleaded not guilty to interstate stalking.

1010 WINS’ Juliet Papa reports

WCBS 880’s Irene Cornell reports from the courthouse

Erbe says she panicked when Nagel posted a crude photo of her teenage daughter on the Internet. The photo is trial evidence. It shows the 14-year-old with a cockroach drawn on her face and a dialogue bubble reading, “I’m ugly,” said Erbe.

Erbe said she fended off a hug from an Nagel, who then stared at her as she completed a scene. She also testified that she received love letters from him that scared her.

“It all made me very upset and worried. I just felt he was obsessed,” she said in a halting voice.

“I got a very bad feeling from him.”

Assistant U.S. Attorney Allon Lifshitz had said in opening statements Tuesday that Nagel relentlessly harassed Erbe, approaching her on filming locations and composing creepy missives about her on the Internet.

When Erbe tried to ignore Nagel, he grew angry and tried to confront her, the prosecutor said.

Defense attorney Robert Datner called his client “an interesting character” who meant no harm. Nagel merely “went to a public place seeking autographs and photographs,” the lawyer said.

Erbe, 44, has starred for nine seasons as Detective Alexandra Eames on the crime series, which now airs on the cable USA Network.

A criminal complaint alleges that in 2008, Nagel traveled to New York with his wife and two children and went to a “Law & Order” filming location where Erbe agreed to pose for a picture with the family.

Nagel, an aspiring songwriter who uses the name “Chaz Rose,” later complained on a social network “that the victim had not responded to a song and letter he had written her, that this was causing him to become angry and that he knew where the program was filming,” the complaint says.

In early 2009, Nagel again went to a filming location and approached Erbe, the complaint says. When she recognized him, she had a security guard tell him to leave.

The complaint says Nagel persisted by writing a letter to Erbe a few months later. It begged her to contact him, saying, “I pray to GOD you will talk to me and end my heartache.”

Nagel also contacted Erbe’s daughter on a social network last March, telling her he was “a harmless romantic who wrote songs” about her mother, the complaint says. The same account was used to send messages to the actress’ brother.

(Copyright 2010 by The Associated Press. All Rights Reserved.)

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