Story highlights Hard feelings remain between Sanders backers and Sen. Barbara Boxer

Tensions linger after an incident at the Nevada Democratic Convention earlier this year

Philadelphia (CNN) A pair of Bernie Sanders supporters confronted Sen. Barbara Boxer Wednesday at her book-signing, accusing the California Democrat of lying about threats she received from other Sanders backers.

California delegate Tyler Morrison and fellow Sanders supporter Maria Estrada confronted Boxer outside the Golden State delegation's breakfast, but staff quickly whisked her back to the book-signing table and asked the two to move on.

"I just wanted to yell at Barbara Boxer for lying about her being threatened in Nevada and then changing the rules in Nevada to get rid of those 56 Bernie delegates," said Estrada, 50, of Compton, California. "She knows what she did, she can try to act like she's ignorant of it, she knows exactly what happened."

The two Sanders backers later got in an argument with a pair of Hillary Clinton supporters in front of the table where the retiring California senator was signing copies of her new book, "The Art of Tough."

"She lied about feeling threatened with her life, that people were intimidating her, yet there's leaked videos of her walking out of the convention taunting the Bernie supporters by blowing kisses at them," said Morrison, 21, of Southern California.

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