"What merits more serious attention is the fact that the unjust acts by the Malaysian side are timed to coincide with the anti-DPRK conspiratorial racket" by South Korea, the Korean Central News Agency said, citing a spokesman at a jurists committee.

The DPRK is the acronym for the North's official name -- the Democratic People's Republic of Korea.

Kim Jong-nam, the half brother of leader Kim Jong-un, was killed on Feb. 13 at an airport in Malaysia after two Asian women wiped an unidentified toxic substance on his face. He was waiting for a flight to his home in Macau.

North Korea has claimed that the dead man is Kim Chol, the name on a passport held by Kim Jong-nam. The KCNA said that a North Korean citizen carrying a diplomatic passport fell into a state of "shock," without mentioning Kim Jong-nam.

Malaysian police said that eight North Koreans are suspected of being involved in Kim's killing. Four of them who fled Malaysia on the day of his death appeared to have already returned to Pyongyang.

They arrested Ri Jong-chol, a 46-year-old North Korean man, and are looking for three others, including a diplomat and an airline employee, who are at large in Malaysia.

Pyongyang blamed Malaysia for pressing ahead with conducting an "illegal and immoral" autopsy, claiming it constitutes an infringement on North Korea's sovereignty and human rights violation.

It also condemned Malaysia for not handing over his body to North Korea.

"This proves that the Malaysian side is going to politicize the transfer of the body in utter disregard of international law and morality," the KCNA said.

South Korea said that it is highly likely that North Korea is behind the latest killing, given that Pyongyang has a track record of committing terrorist attacks and inhumane acts.

North Korea said that Seoul has shown an "excessive response" to the death by linking it to security concerns.

"This proves that the South Korean authorities have long expected the case since it worked out a scenario for it," it said.

The incident has developed into a diplomatic row between Malaysia and North Korea, which have maintained a close diplomatic relationship for more than 40 years.

North Korea's top envoy to Malaysia Kang Chol has claimed Malaysia colluded with Seoul in investigating the case.

Malaysia denounced his comment as "diplomatically rude," stressing that the investigation is fair.

North Korea said that it is ready to send a delegation of jurists for a joint probe, but Malaysia rejected it.

South Korea's unification ministry dismissed North Korea's claim as preposterous, saying that it is not even worth countering.

Experts said that North Korea is maneuvering to leave Kim's mysterious death unresolved as it apparently moves to handle the issue from a legal perspective.

"As Kim's death has made international headlines, North Korea could not continue to shun the issue," said Kim Keun-sik, a professor at Kyungnam University.

"Pyongyang seeks to deny allegations linking to its leader while blaming South Korea and the international community for staging what it called an anti-North Korea conspiracy," he said.

Kim Jong-nam had been living in foreign countries for years after apparently falling out of favor with his father for attempting to enter Japan with a fake passport in 2001.

North Korean defectors said that ordinary North Koreans are not aware of Kim's existence as the regime has tightened control over information about the Kim family.

In a patriarchal society like North Korea, the first son is widely viewed as the successor, but the power was given to Kim Jong-un, who is the third son. He assumed power in late 2011 following the sudden death of his father.

Seoul's spy agency said that the incumbent leader has issued a "standing order" to kill his half brother since he took power. (Yonhap)