Transcript for Video appears to show assassination of North Korean leader's half-brother

Their funerals held today. Tom? Thank you. And now to what appears to be the assassination of the brother of Kim Jung un. Here's Matt Gutman. Reporter: All it took was 2.3 seconds to deliver death. Tonight, grainy airport security video obtained by a Japanese TV station purportedly showing a single swift move in which one of the women sneaks up on Kim jung-nam from behind and covered his face with a cloth laced with a liquid. It was poison. Moments later, this image showing Kim jong-nam desperately seeking help from airport security. He died minutes later on the way to the hospital. There's every indication based on North Korea's history that this was a targeted kill. Reporter: Police say these two women are the killers, one of them in the now infamous "lol" shirt. Police say CCTV video shows her tracking Kim jong-nam through the Kuala Lumpur airport. Both now under arrest. Investigators say the other woman claims she thought she was part of a comedy show prank. Authorities have conducted two autopsies on the man with the playboy reputation. ABC news has learned he enjoyed frequenting places like this Singapore girls' bar, but north Korea has rejected the autopsies. There's a manhunt for four suspects in Malaysia. Authorities think this has many of the characteristics of a north Korean purge. Remember, North Korea's leader, Kim Jong-un is accused of killing his own uncles and others. Thank you. To Iraq, and a new wave of military attacks to retake mosul from ISIS.

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