The police believe two North Korean men wanted to assist investigations into the murder of Kim Jong-nam are still within the North Korean embassy's compound in Bukit Damansara, here.

Inspector-General of Police Tan Sri Khalid Abu Bakar who confirmed the matter to Bernama News Channel (BNC) through a WhatsApp message said the two men were the North Korean Embassy's second secretary, Hyon Kwang-song, 44, and North Korean airline Air Koryo's staff, Kim Uk-il, 37.

When asked why the police did not raid the embassy to arrest the two men, Khalid said the police had to respect the Vienna Convention which protected the embassy grounds through diplomatic immunity and could not be compromised.

He said an arrest warrant had already been issued for Uk-il last week, while the secretary had immunity to arrest.

On the four suspects who left the country immediately after Jong-nam was poisoned, he said, "there have been no further developments received from Interpol".

Jong-nam, who entered the country using a passport bearing the name Kim Chol, died after his face was wiped with the VX nerve agent while waiting to board a flight to Macau at klia2 on Feb 13.

Two foreign women were charged for the murder at the Sepang Magistrate's Court here on March 1.

Siti Aisyah, 25, an Indonesian and Vietnamese Doan Thi Huong, 29, along with four others still at large, were charged with murdering Jong-nam, 45, at the departure hall of klia2, at about 9am.

In the meantime, Khalid declined to comment on foreign media reports saying Japan had provided fingerprint data to the police to verify Jong-nam's identity.

"I will only comment if the news is released by the official Japanese authorities" he said.

The report said Japan had provided fingerprints and some other data to Malaysia to assist the investigation into the murder of Jong-nam, the estranged half-brother of North Korean leader Kim Jong-un.

The Kyodo news agency quoted Japanese government sources as saying the fingerprint information was obtained by Japanese immigration authorities when Jong-nam was arrested at Narita International Airport in 2001 while attempting to enter the country with a fake passport.

-- BERNAMA