The case against Siti Aisyah, one of the two women charged with murdering North Korean dictator Kim Jong-un’s half-brother with a chemical weapon in February 2017, was suddenly released and sent home to Indonesia on Monday. Aisyah has been jailed in Malaysia for the past two years as the prosecution moved forward.

Prosecutors gave no reason for dropping the charges. Aisyah herself professed to be “shocked” by her sudden freedom.

CNN reported behind-the-scenes lobbying by the Indonesian government played a role in securing Aisyah’s freedom:

Rusdi Kirana, Indonesia’s ambassador to Malaysia, said the decision to drop the case against Aisyah followed months of lobbying by Jakarta. The Indonesian Law and Human Rights Ministry released an image of an undated letter in which it requested that Aisyah be freed.

The letter repeated many of the arguments made by her defense attorneys. It also asked that Malaysian authorities take into account the two countries’ “good relations” when considering the request.

Malaysian Attorney General Tommy Thomas responded with his own letter Friday, announcing that the prosecution would effectively drop the case. Copies of both letters were released by Indonesian authorities and a spokesman for Thomas confirmed their validity.

Asiyah and her family publicly thanked Indonesian President Joko Widodo for securing her release. Asiyah additionally thanked the Malaysian government and the lawyers who represented her.

The BBC quoted a letter from Malaysia’s attorney general to Indonesia’s law minister in which Jakarta’s objections to the prosecution of Asiyah and the good state of relations between the two countries were taken into account when deciding to drop the charges.

CNN’s report implies Aisyah’s prosecution dragged on for so long because Malaysia was nervous about antagonizing the North Korean government by releasing her. Aisyah and her co-defendant, Doan Thi Huong of Vietnam, were portrayed by their lawyers as innocent dupes who thought they were participating in a prank television show and did not realize the lotion they rubbed on Kim Jong-nam’s face contained a deadly nerve agent.

Interpol is attempting to track down the four North Korean agents accused of orchestrating the murderous “prank.” A “red notice,” the functional equivalent of an international arrest warrant, was issued for the four in March 2017, but their whereabouts remain unknown.

Malaysian prosecutors are expected to decide by Thursday if they will drop the charges against Huong, who cut a press conference short on Monday because her lawyer said she was “traumatized by the unfair decision” to release Aisyah without releasing her as well.

According to the BBC, there was “less evidence” against Aisyah than there is against Huong, so the latter’s release may not be a foregone conclusion.