South Korea's defense chief said Monday that North Korea's alleged assassination of its leader Kim Jong-un's half brother appears to be part of Pyongyang's move to remove any potential challengers to Kim's power and forestall any outside attempt to overthrow its regime.
"The murder of Kim Jong-nam by the North can be meant to remove alternative forces to the Kim Jong-un regime and warn the international community against any possible regime change attempts," Defense Minister Han Min-koo told the parliamentary National Defense Committee.
The assassination also appears to be aimed at delivering "a strong warning against North Korean defectors and dissidents," he said.
The minister estimated one of five reported poisons -- neostigmine, potassium cyanide, ricin, tetrodotoxin or nerve agent -- was used to assassinate the elder half brother of the North's leader in Malaysia last Monday.
Pyongyang is likely to have about 40 biological and chemical weapons, he said.
The military will remain vigilant against possible provocative acts from the North following the incident, Han said, adding there is no unusual movement in North Korean military.
Agents belonging to North Korea's spy agency, the Reconnaissance General Bureau, are widely believed to have carried out the murder at Kuala Lumpur airport on Feb. 13. Kim Jong-nam, once tipped as a possible successor to his late father Kim Jong-il, has been critical of the North Korean regime. (Yonhap)