Khan was addressing a massive gathering of Pakistani-Americans when the Baloch youths suddenly stood up from their seats and started raising the slogan.
Balochs living in the US have been raising their voice against alleged atrocities, disappearance and human rights violations in Balochistan by Pakistani security forces.
For the last two days, they have been running a mobile billboard campaign urging President Donald Trump to help end "enforced disappearances" in Pakistan.
The three Baloch youths who were raising anti-Pakistan slogans were far away from the main podium, where Khan was speaking. He could continue his address uninterrupted. About two minutes-and-half later, local security personnel forced them to leave the indoor auditorium.
A few supporters of Imran Khan were seen pushing them from behind and asking them to leave the arena.