An odorless chemical with the consistency of motor oil, VX is an extremely powerful poison, with an amount no larger than a few grains of salt enough to kill. It can be inhaled, swallowed or absorbed through the skin. Then, in anywhere from a few seconds to a few hours, it can cause a range of symptoms, from blurred vision to a headache.
Enough exposure leads to convulsions, paralysis, respiratory failure and death.
The killing of Kim Jong Nam took place amid crowds of travelers at Kuala Lumpur's airport and appeared to be a well-planned hit. Kim died on the way to a hospital, within hours of the attack.
Also Saturday, police confirmed that a raid earlier in the week on the outskirts of Kuala Lumpur was part of the investigation. Abdul Samah, the police official, did not specify what authorities found there, but said the items were being tested for traces of any chemicals.