A man claiming to be the son of the North Korean leader's slain half brother said he and his family are safe and in an undisclosed location, in a video released online.
"I'm currently with my mother and my sister," said the man said in a clip posted to YouTube. "We hope this gets better soon," he added.
A South Korean intelligence official identified the man as 21-year-old Kim Han Sol, the son of Kim Jong Nam's second wife who lives in Macau.
The video was posted by a group called the Cheollima Civil Defense, which says it works to help high-level North Korean defectors.
In a statement accompanying the video, the group thanked the governments of the Netherlands, China, the United States and a "fourth unnamed government" for providing assistance to protect the three.
Kim Jong Nam was killed in the Kuala Lumpur International Airport on February 13 by assassins using a toxic nerve agent.
Authorities in Malaysia have since charged 25-year-old Indonesian Siti Aisyah and 28-year-old Doan Thi Huong, from Vietnam, with murder for allegedly swiping Kim's face with VX nerve agent while he waited to board a flight home to Macau. He died 20 minutes later.
Malaysia has blamed North Korea for organizing the killing and is seeking additional suspects in the case.
Kim Jong Nam was estranged from North Korean leader Kim Jong Un. He reportedly fell out of favor with their father, the late Kim Jong Il, in 2001, when he was caught trying to enter Japan on a false passport to visit Tokyo Disneyland.