A notorious professional protester with past ties to multiple controversial anti-Israel efforts was spotted among the rioters who broke into a Columbia University building and occupied it this week, according to police.

Lisa Fithian, 63, was captured in footage taken outside Hamilton Hall — an academic building on the Ivy League’s Morningside Heights campus that protesters, some of them masked, stormed the around 12:30 a.m. on Tuesday.

A lifelong agitator, Fithian in the mid-2010s was raking in $300 per day training unions and other activist groups in the basics of demonstration and disruption, Mother Jones reported in 2012.

Lisa Fithian was spotted in footage taken from outside Hamilton Hall this week.@jessicaschwalb7/X

She has frequently thrown her energies behind pro-Palestinian causes — and even celebrated her birthday earlier this month in Istanbul, Turkey, where she was “training the participants on the next Flotilla to Gaza in the coming week,” according to an Instagram post.