Is there an obligation to tear clothing at the funeral of Maran Rav Gershon Edelstein?

Is there an obligation to tear clothing upon hearing the news or at the time of the funeral?

The students are required to tear. It is akin to the tearing for one's father and mother.

One must tear the upper garment, and preferably tear on the left side until reaching the heart. It is permissible to start the tear with a tool and continue by hand.

The Shulchan Aruch, Yoreh De'ah, laws of tearing, Siman 340, Paragraph 7:
For a sage and a Torah scholar who is asked about a law anywhere and he states it, one tears for him even after burial, on the day of hearing, if it is within 30 days. And one tears for him during his eulogy. If one did not tear on the day of hearing, and the time of eulogy has passed, and he did not tear, he no longer tears. And they tear until they reveal their heart. It has already been customary for Torah scholars everywhere to tear for each other a handbreadth, even if they are equal and none teaches the other. The Rema writes: "There is an opinion that one does not tear for a sage unless he is his teacher or they know his innovations, that is, his teacher, and so it is customary to be lenient in these lands." The Shulchan Aruch, Siman 340, Paragraph 8: for one's teacher from whom most of his wisdom comes; if Scripture, Scripture; if Mishnah, Mishnah; if Gemara, Gemara; he tears all his garments until he reveals his heart.