Weeks after the estranged half-brother of North Korean supreme leader Kim Jong Un died suddenly after having a substance wiped on his face by two young women in an airport in Malaysia, North Korean officials are offering an alternate theory to the one presented by Malaysian law enforcement: it must have been a “heart attack.”

Video of the young woman approaching Kim Jong Nam from behind and apparently smearing a substance on his face before running away to wash her hands has been making the rounds on news sites for weeks, and although North Korea demanded that no medical examination be conducted to aid in the investigation of the Jong Nam’s death, Malaysian authorities thought it best to do so anyway – and their efforts proved worth it, finding a banned chemical substance and highly toxic nerve agent known as VX smeared in the man’s mouth and eyes.

Malaysia has charged the two women with murder and has been seeking interviews with at least seven North Korean men.  Two of the suspects are said to be holding up inside the North Korean embassy, with four others already fleeing back to their reclusive nation.  North Korea has offered no assistance to Malaysian authorities, opting instead to hinder the investigation every step of the way – including their latest declaration that Kim Jong Nam must have died of a heart attack… despite not having any access to the body thus far in order to establish such a theory.  Stranger still, the North Korean delegation refuses to acknowledge the identity of the man, despite citing Kim Jong Nam’s medical records as evidence to support their stance.

“He has a record of … heart disease,” Ri Tong Il, a spokesman for the North Korean delegation, told reporters outside the North Korean Embassy. “Therefore, this is a strong indication that the cause of the death is a heart attack.”

Ri went on to question the veracity of the report indicating that VX was used to kill Jong Nam.  According to him, the two women charged with his murder should have also fallen ill after coming into contact with the substance. “They are the ones who directly contained the liquid on their palms of the hands to apply to the face.”

Experts have indicated that VX is a difficult substance to synthesize, but could be handled by a government level laboratory such as those employed by the North Korean regime.  Kim Jong Un, North Korea’s third leader since his grandfather led a revolution that sparked the Kim dynasty, had good reason to order his brother’s death, not the least of which being that Kim Jong Nam was once expected to take control of the nation upon his father’s death, until he lost Kim Jong Il’s favor when caught trying to enter Japan illegally with his family to visit Disneyland.

Kim Jong Un has struggled to develop the level of respect for his reign that his father and grandfather enjoyed, and has been accused of executing many top-level officials as a part of his efforts to consolidate power and influence within the nation.  Kim Jong Nam, on the other hand, has lived almost entirely outside of the North Korean state since his mishap in China, and has openly criticized some of North Korea’s policies.

In the eyes of many North Koreans, Kim Jong Nam, the older brother and first choice for the role of Supreme Leader’s words may still carry weight, a likelihood Kim Jong Un could not tolerate as he purged his administration of respected leaders that treated his perception as a deity-like head of state.