Kim Jong-nam
© Shin In-seop/JoongAng Ilbo via AP, File
In this June 4, 2010, file photo, Kim Jong-nam, the eldest son of then North Korean leader Kim Jong-il, waves after his first-ever interview with South Korean media in Macau. The murder of North Korean leader Kim Jong-un’s estranged half-brother
The murdered half-brother of North Korean dictator Kim Jong-un had been a CIA informant and was killed while on a trip to meet his contact person, the Wall Street Journal reported Monday.

Kim Jong-nam had met on several occasions was CIA operatives and "almost certainly" was in contact with other nation's intelligence services, including China's, the Journal reported, citing "a person knowledgeable about the matter."

Kim Jong-nam was killed at a Malaysian airport in 2017 by two women who rubbed his face with a fatal nerve agent, and North Korea was widely blamed.

The CIA, according to the Journal, was relieved that his assistance didn't come out in the wake of that killing. Rather than hailing killing of a CIA spy, North Korea has denied responsibility.

"There was a nexus" between the CIA and Kim Jong-nam, the source told the Journal, adding that he was in Malaysia in February 2017 for a meeting there with his CIA contact.

The Journal reported that few specific details are known about how Kim Jong-nam aided the CIA. Several former U.S. officials told the paper though, that because he had lived abroad for many years, mostly in the Chinese territory of Macau, he likely had little inside knowledge of the reclusive Communist regime.

His role as a CIA informant, according to the Journal, will also be outlined in a book being published Tuesday called "The Great Successor," by Anna Fifield of the Washington Post.