A former employee of the Stanford Linear Accelerator Center was arrested Monday for allegedly destroying $500,000 worth of protein crystal samples at the lab, the FBI announced.

Silvya Oommachen, 32, is accused of removing 42 cassettes, each containing 96 separate crystal samples, from cryogenic containers and placing them on a lab table, according to a complaint filed by FBI Special Agent Matthew Quick.

Left at room temperature, the crystal samples, sent from scientists or technicians to be examined at SLAC, were ruined, SLAC spokesman Robert Brown said.

Oommachen had worked at the Joint Center for Structural Genomics laboratory at SLAC until earlier this month when her employment was terminated because she hadn't shown up for work since June 17, FBI spokeswoman Patti Hansen said.

Quick, who interviewed Oommachen after her arrest, said in his complaint that Oommachen had stated she felt overworked and could not handle working at the lab anymore.

Along with the crystals, Oommachen allegedly left three yellow Post-it notes with a smiley face that read, "Performed by X Black," which Oommachen allegedly later explained was her alter ego, according to the complaint.

She allegedly claimed she felt "bad karma" associated with her job at the lab, and that she believed the lab was not being environmentally responsible by keeping so many protein samples in storage.

She said she thought that destroying some of the protein samples would reverse some of the bad karma she was experiencing, according to the complaint.

She also allegedly said she believed 90 percent of the protein that she destroyed was old and no longer scientifically useful, according to Quick.

Oommachen was arrested at her home Monday and was scheduled to be arraigned in federal court in San Francisco Tuesday morning, FBI spokeswoman Patti Hansen said.

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— Bay City News Service