USA government sources have told Reuters they believe he had been murdered by North Korean agents.
Malaysian police officers stand outside Putrajaya Hospital, outside Kuala Lumpur, where the body of Kim Jong Un's brother was initially brought. Malaysian authorities, meanwhile, have arrested a suspect in the crime.
The assassination plot involving Kim Jong-nam, was discussed at a high-level ministerial meeting here today.
South Korea's foreign ministry said it could not confirm the reports, and the country's intelligence agency could not immediately be reached for comment.
Police reports said the two female agents fled in a taxi and were being sought by Malaysian police. The airport is in Selangor, near Kuala Lumpur.
Kim, who had not yet passed through security, was preparing to take a late-morning flight on Monday from the Malaysian capital to his home in killed-in-malaysia-1487072747">Macau when he was allegedly attacked, according to South Korean MPs briefed by security services.
Jong Nam, estranged from the reclusive North Korean regime, was pronounced dead after being rushed to a hospital.
"According to [Lee]. there was one [assassination] bid in 2012, and Jong-nam in April 2012 sent a letter to Jong-un saying 'Please spare me and my family, '" Kim Byung-kee, a member of the parliamentary intelligence committee, told reporters. He is believed to have been born May 10, 1971. The killers, suspected North Korean agents, used a toxin "more potent than cyanide" to eliminate Kim, an outspoken critic of his younger's brother's rule. But the North Korean spy agency apparently continued searching for an opening to eliminate him.
South Korean media say the half-brother of North Korean leader Kim Jong Un has been killed in Malaysia.
He claimed he wanted to visit Disney's Tokyo resort, but the incident embarrassed his father, and the then North Korean leader was succeeded by Kim Jong-Un in December 2011.
Journalists at the hospital said North Korea's ambassador to Malaysia, Kang Chol, and colleagues arrived at the hospital in the early afternoon and remained there into the evening.
News of the murder comes two days after Kim Jong Un test-fired a ballistic missile as part of efforts to develop North Korea's nuclear-weapons capability.
Jang, as the vice chairman of the power National Defense Commission, had been a virtual "number two" to Kim and was close to China, North Korea's longtime benefactor. Kim Jong Nam is also the eldest son of former leader Kim Jong Il. She has not been seen in public for more than three years, Gause said. That's when Kim Jong-il began grooming another one of his four known sons, Kim Jong-un, to take the throne.
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