KAJANG: The Vietnamese woman who was tried for the killing of the estranged half brother of North Korea's leader was released Friday from a Malaysian prison and due to fly back to Hanoi later in the day, her lawyer and an embassy translator said.

Doan Thi Huong's release likely closes the case, since four North Koreans named as co-conspirators in the 2017 slaying are not in custody. Malaysian officials never officially accused North Korea and made it clear they didn't want the trial politicized.

Vietnamese embassy translator Maridam Yacfar told reporters at the prison that Doan Thi Huong looked "happy" but couldn't give further details.

Huong's lawyer, Hisyam Teh Poh Teik, said Huong went to an immigration office and will fly back to Hanoi later Friday.

Huong (30) pleaded guilty to a lesser charge of causing injury last month after prosecutors dropped the murder charge against her. She was sentenced to 40 months in prison from the day of her arrest and was released early for good behaviour.

Huong was the last suspect in custody after the Malaysian attorney general's stunning decision in March to drop the murder case against her co-defendant, Indonesian Siti Aisyah, following high-level lobbying from Jakarta. Huong sought to be acquitted after Aisyah was freed, but prosecutors rejected her request. Aisyah returned home to Indonesia.

The two women were charged with colluding with the four North Koreans to murder Kim Jong Nam with VX nerve agent. The women smeared the substance on his face in the Kuala Lumpur International Airport on February 13, 2017, and have said they thought they were taking part in a harmless prank for a TV show.

The four North Koreans fled Malaysia the day Kim was killed.

The High Court judge last August had found there was enough evidence to infer that Aisyah, Huong and the four North Koreans engaged in a "well-planned conspiracy" to kill Kim and had called on the two women to present their defence.

Lawyers for the women have said that they were pawns in a political assassination with clear links to the North Korean Embassy in Kuala Lumpur, and that the prosecution failed to show the women had any intention to kill. Intent to kill is crucial to a murder charge under Malaysian law.

Hisyam said Huong was very joyful when he met her at the prison on Thursday.

"She was smiling from ear to ear. She is looking forward to return home to meet her family and friends," he told The Associated Press.

After her sentencing last month, Huong told reporters at the court room that she wants to "sing and act" when she returns to Vietnam.

Kim Jong Nam was the eldest son in the current generation of North Korea's ruling family. He had been living abroad for years but could have been seen as a threat to Kim Jong Un's rule.