KUALA LUMPUR, Feb 24 — Police seized an undisclosed number of chemicals from a condominium in Jalan Klang Lama on Wednesday, according to an agency source after it was revealed that the VX nerve agent was used to kill Kim Jong-nam.

According to The Star newspaper, police also arrested a Malaysian man during the raid over suspicions that he may be involved in the alleged assassination of the half-brother to North Korea’s leader, Kim Jong-un.

Police also recovered chemistry equipment and protective gear from the condominium.

"Police are not ruling out the possibility that the Malaysian man might have expertise in chemistry,” a source was quoted as saying.

Inspector-General of Police Tan Sri Khalid Abu Bakar today revealed that the chemical weapon was used to kill Jong-nam and said investigators are trying to determine how the powerful neurotoxin was brought into Malaysia.

The toxin is classified as a weapon of mass destruction according to international conventions. Restrictions on its production and storage make the substance rare and available only to highly-militarised states.

Jong-nam was attacked by two women at the KL International Airport 2 (KLIA2) on February 13 while waiting for a flight to Macau. He died on the way to hospital.

Police previously arrested four people including three foreigners over the killing, but released the local man on bail.

They have also identified seven North Koreans as suspects including one senior official from the country’s embassy to Malaysia who has since fled home.