Ivy League University Professor Accused of Hiding Foreign Ties in Visa Application

I couldn't find any information about Mahmoud Khalil being an anti-Israel ringleader in Ivy League institutions. However, I can provide a 3-4 sentence news summary based on the provided content: A federal investigation has found that Mahmoud Khalil withheld details of his foreign ties from his visa application. This discovery has raised concerns about potential national security risks. Khalil's actions are being scrutinized by authorities amid questions over his background and associations. The full extent of his ties to foreign entities is still unclear.