The first sticker, observed by students on Tuesday, read “Don’t be Mahmood Khalil,” referring to Mahmoud Khalil, the former ...

The university did not release the names of students who were disciplined, nor did it say how many students faced punishments. Stickers posted by pro-Palestinian groups on the Columbia campus.

Federal law enforcement had executed a search warrant on Thursday night as part of a separate probe into whether Columbia University harbored undocumented immigrants on its campus. Stickers posted ...