The London Telegraph reported that the alleged murder plot may have been the work of a faction loyal to Kim Yong Chol, a four-star general demoted last year before being restored to his previous rank and rehabilitated.
The Telegraph cited the JoongAng Ilbo newspaper as reporting that an exchange of gunfire in Pyongyang last November may have signaled the attempt.
The Express, meantime, quoted a source as saying:
"It appeared that disgruntled people inside the North moved before the time of the demotion of Kim Yong Chol."
GlobalPost senior correspondent in Korea, Geoffrey Cain, warns readers to take the news with a grain of salt.
"Nobody knows for sure whether anybody really tried to assassinate Kim Jong Un, or if this amounts to speculation from the South Korean intelligence agency," Cain said from Seoul.
The original JoongAng daily report cited an anonymous intelligence source, which is a common practice in South Korea as a condition for getting interviews.
"Beyond that," Cain said, "the allegations can't be corroborated yet."
If anything, many experts say that Kim Jong Un has turned out to be a more powerful leader than originally thought, adept at dealing with the military power holders who can, if they want, be antagonistic.
Gen. Kim Yong Chol, who the press suggested was behind the assassination attempt, was until recently considered one of the closest allies of Kim Jong Un.
He was reportedly behind the sinking of the South Korean corvette Cheonan in March 2010 and the deadly bombing of South Korea's Yeonpyeong Island later that same year.
North Korea analysis website, 38 North, points out that Gen. Kim's Reconnaissance General Bureau (RGB) has become more prominent recent years, and NK Leadership Watch, another DPRK analysis site, notes that Gen. Kim is reportedly difficult to manage.
But GlobalPost's Cain says "that's not enough evidence to suggest that an assassination really happened.
A power struggle between the intelligence department of the ruling Workers' Party and a division of the Ministry of the People's Armed Forces resulted in Gen. Kim's demotion last year.
However, the general appeared to have since been accepted back into Kim Jong Un’s inner fold. He was promoted back to his original rank and even appeared alongside the young leader at a recent musical recital.