The threat has purportedly come from a user named Farman Khan whose account has accessed from Dubai. He has also received abuses from Bilal Ahmad, presumably a resident of Pakistan.
"If given an opportunity, I would kill Kumar with my own hands," Khan wrote on Kumar's time line.
"Friends I am receiving threats, but I am happy that the enemy camp is in complete doldrums and if someone wants to kill me, I swear on my motherland and martyrs, that in case he happens to come face-to-face, I will give him hell," Kumar wrote on Facebook.
The video of the patriotic poem penned and recited by Kumar was uploaded by him on Kargil Day (July 26), but went viral aftermath of the Uri attack.
"Abki yudh hua to Kashmir to rahega par Pakistan nahin hoga" (if there is another war, Kashmir will survive but Pakistan won't) and "hum Pakistan ke bomb se nahin, Tashkent aur Shimla samjhauton se darte hain" (We are not scared of Pakistan's bombs but of Tashkant and Shimla pacts) and reminds Pakistan of its defeats in the hands of the Indian army in 1965, 1971 and 1999," read the poem.