Rebecca Koster, left, was the victim of a murder allegedly...

Rebecca Koster, left, was the victim of a murder allegedly committed by Evan Ganthier, right. Credit: Handout, Handout

On the last night that a pretty, young Medford woman was seen alive, she and her friends were the targets of intense attention from a man at a Holbrook bar, a Suffolk prosecutor told jurors Wednesday.

The next time Rebecca Koster, 24, was seen by anyone other than that man -- Evans Ganthier, 33, of Port Jefferson Station -- she was dead, on fire, mutilated and wrapped in sheets, blankets and garbage bags by the side of a Connecticut back road, Assistant District Attorney Janet Albertson said during her opening argument in a packed courtroom.

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On the last night that a pretty, young Medford woman was seen alive, she and her friends were the targets of intense attention from a man at a Holbrook bar, a Suffolk prosecutor told jurors Wednesday.

The next time Rebecca Koster, 24, was seen by anyone other than that man -- Evans Ganthier, 33, of Port Jefferson Station -- she was dead, on fire, mutilated and wrapped in sheets, blankets and garbage bags by the side of a Connecticut back road, Assistant District Attorney Janet Albertson said during her opening argument in a packed courtroom.

Ganthier is charged with second-degree murder in the Dec. 4, 2009, killing.

Koster was out with friends the night of Dec. 3 at Butcher Boys Bar & Grill in Holbrook. Ganthier was there, "obviously, aggressively hitting on girls," Albertson said. Koster, in particular, drew his attention, even though her boyfriend was with her, Albertson said.

After she arrived home, Ganthier called her cellphone shortly before 4:30 a.m. and she agreed to meet him.

"Rebecca Koster made a very foolish mistake, as a young girl," Albertson said. "We do know that her mistake was fatal."

The next person who saw her was Russell Morrison, who was driving on Jeremy Hill Road to his home in Stonington, Conn., about 7:15 p.m.

"It's really a back road," he testified Wednesday. "It's dark, quiet and sleepy." He said he saw what seemed to be a brush fire, but when he looked closer, it appeared to be a body.

The audience included District Attorney Thomas Spota and members of both Koster's and Ganthier's families. Ganthier blew a kiss to his family as he entered the courtroom.

Koster's stepfather, Larry Ross, said he was glad the trial finally was underway.

"I just want justice for my daughter," he said.

Defense attorney William Keahon cautioned jurors that the case may not unfold the way Albertson says and reminded them that Ganthier is presumed innocent.

"I intend to bring out facts which the district attorney chooses not to," he said.

It was days before the body was identified as Koster's through dental records. In the meantime, Albertson said, her family got texts from her phone in which someone posing as her claimed to be held captive by her boyfriend. Police searched his house and found no one.

Police were led to Ganthier by the calls he made to Koster's phone and by two thumbprints on duct tape wrapped on her body, Albertson said.

Ganthier later told police that he just wanted to talk to Koster that night, and wasn't interested in sex or drugs with her. Albertson scoffed at that.

"It wasn't the left side of his brain he was interested in stimulating," she told jurors.

Ganthier then told detectives Koster tripped, fell and hit her head while walking in his garage. She died soon after and he panicked, so he cut off all her fingers, toes, ears, nose and a tattoo of a butterfly on her back, he told detectives, Albertson said.

He took her remains on the Port Jefferson ferry to Connecticut, doused her body with gasoline and left it for Morrison to find, Albertson said.

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