(CNN) -- Two New Jersey men arrested last week at John F. Kennedy International Airport allegedly on their way to fight with an al Qaeda-affiliated group in Somalia were followers of an extreme Islamist group based in New York, CNN has learned. CNN has obtained an image of the two suspects, Mahmood Alessa and Carlos Eduardo Almonte, attending a protest in New York organized by the Islamic Thinkers Society on June 1 of this year. They appear to have been taking part in a demonstration against Israel. One is holding a banner, the other an Islamic Thinkers Society poster that includes the slogan, "Exterminate the Zionist Roaches." The society's video of the event, posted on its YouTube channel, has since been removed.
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Mahmood Alessa and Carlos Eduardo Almonte spotted at earlier rally
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Men appear to be followers of al Qaeda-supporting Islamic Thinkers Society
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"Our struggle is always intellectual & political non-violent means," group says
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Suspects in several other terror-related cases also have ties to group
According to counterterrorism officials they also organize private gatherings in the greater @placeholder area.