Cornell University police are investigating a series of antisemitic threats made against the school’s Jewish community in online posts over the weekend, its president announced.

At Cornell, security will continue to be heightened in the wake of the threats, according to a statement from Joel M. Malina, vice president for university relations.

Pro-Israel Cornell University students signed a petition demanding their their school fire the anti-Israel singer it hired to perform at its end-of-the-year concert this May.