Kim Jong Nam died on February 13 after being smothered at the airport's budget terminal with VX nerve agent, classified by the United Nations as a weapon of mass destruction.
Since then, tens of thousands of people have passed through the terminal, with the location of the assault remaining accessible.
The police forensic team, fire department and Atomic Energy Licensing Board swept the budget terminal of Kuala Lumpur International Airport (KLIA2) at 1 am on February 26 (1700 GMT on February 25). "We confirm, number one, there is no hazardous material found in KLIA2, number two, KLIA2 is free from any form of contamination of hazardous material and thirdly, KLIA2 is declared a safe zone," Abdul Samat Mat, the police chief of Selangor state who is leading the investigation, told reporters at the airport.