Kim Jong Nam was assassinated with a nerve agent in February 2017, reportedly after having met with his CIA contact in Malaysia.
Siti Aisyah, an Indonesian national, was freed after Malaysian prosecutors withdraw charges against her.
A self-described "hacktivist" created the @juche_school1 Twitter handle and named the account "Bloody Rocket Kim."
"Salivation, tears, urinating on yourself, sweating, diarrhea, throwing up...all of that's going to happen."
South Korean media alleged China stopped a North Korean plot to kill Kim Jong Un's nephew, Kim Han Sol, months after his father was killed in Malaysia.
Police considered four other North Korean citizens as suspects in the murder but their names were not made public.
A report based on interviews with 375 defectors identified up to 333 killing sites in the hermit state.
Tensions are high between the two nations after a relative of the North Korean leader was poisoned and died in Kuala Lumpur.
Earlier speculation suggested it may have had something to do with marking the birthday of the deceased founder of the country.
North Korea celebrates its founder's birthday on Saturday and has tested missiles on significant occasions in the past.
North Korea's Asian Cup tie with Malaysia has been postponed.
China said that international action should wait until the investigation is complete.
A man claiming to be Kim Han Sol released a video saying that he is in hiding with his mother and sister.
Malaysian police investigating the murder of Kim Jong Nam questioned up to three men hiding in the North Korean embassy.
Relations have deteriorated since the assassination of Kim Jong Nam in Kuala Lumpur.
Kim Jong Un's reign has been one of "terror", say South Korean Intelligence Service.
N. Korea has artillery within range of Seoul armed with WMD shells.
Diplomat is one of eight Koreans under investigation after apparent assassination of Kim Jong Nam.