It’s an Israeli Independence Day custom.
This has been done since the Ponavezher Rov, HaGaon HaRav Yosef Shlomo Kahaneman ZT”L established the yeshiva.
This year, there were two changes.
First off, the flag pole was extended to make it higher – fearing Bochrim from the Peloeg would try and sabotage the flag. Additionally, as can be seen in the video, Bochrim from Ponavezh also tried hanging the “Degel Hatorah Party” flag next to the Israeli flag.
(YWN Israel Desk – Jerusalem)