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The Twilight Saga community is mourning the loss of 53-year-old fan Gisella G., who died this morning in anticipation of attending Breaking Dawn: Part 2's celebrity panel at Comic-Con later this week. 

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"I'm so sorry to hear the devastating news about Gisella G," tweeted Ashley Greene. "My thoughts and prayers are with her family and friends."

"This is horrible," Nikki Reed writes. "So sad. I'm speechless."

According to San Diego police, the attendee reportedly tried to run across a crosswalk to secure her place in line when the unidentified driver of a Subaru Outback didn't see her in time. Unconscious and suffering a bleeding head wound, Gisella was taken to the hospital where she later died.

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The film's producers (on behalf of Lionsgate and Summit) released a joint statement shortly after, offering their condolences. "The entire Twilight community [is] saddened by the death of a Comic-Con fan today due to a traffic accident during the hours leading up to this year's convention in San Diego. ”

In the hours since the fan's tragic death, an online petition has been set up asking for a moment of silence for the deceased fan during the Breaking Dawn: Part 2 panel.

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Comic-Con starts on Thursday, July 12 and runs through Sunday, July 15. Robert Pattinson, Kristen Stewart, Taylor Lautner and more of the Breaking Dawn: Part 2's stars are confirmed to attend.