BOSTON (CBS) – A survivor of the 2013 Boston Marathon bombings confronted a supporter of Dzhokhar Tsarnaev outside court Thursday morning. Adrianne Haslet was heading into the First U.S. Circuit Court of Appeals when the encounter happened.

She saw a protester holding a sign that said “Free Jahar,” the nickname for the convicted bomber. She flashed an obscene gesture and said something quickly to him before continuing into court.

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Adrianne Haslet confronts of a Dzhokhar Tsarnaev supporter outside court (WBZ-TV)

The court is hearing arguments over whether Tsarnaev got a fair trial. His lawyers are arguing that his case should never have been tried in Boston, but prosecutors insist he got a fair trial from a fair jury.

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The attack killed three people and injured more than 260. Haslet, who lost part of her leg in the bombing, addressed the issue on Instagram before the hearing.

“Arguing that this a–hole did not get a fair trial because he was tried in the same city he tried to destroy is like a toddler saying he is angry his mom saw him knock over his brother’s LEGO’s in their shared living room,” she wrote.

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Haslet added that she would “testify again in a heartbeat.”