A year since his audacious assassination in a crowded Malaysian airport, justice remains elusive for Kim Jong Nam, the estranged half-brother of North Korean leader Kim Jong Un.

While the prosecution is expected to wrap up their case soon in the trial of two women charged with his murder, the alleged real masterminds -- North Korean agents -- remain scot free despite anecdotal evidence and security camera images offering tantalizing hints of their involvement.

Indonesian Siti Aisyah, 25, is jointly charged with Doan Thi Huong, 29, from Vietnam, and four other North Korean men still at large with the murder of Kim Jong Nam on Feb. 13 last year at Kuala Lumpur International Airport's budget terminal.

The women have pleaded innocent. The prosecution named the four North Koreans as Hong Song Hac, 34, Ri Ji Hyon, 33, Ri Jae Nam, 57 and O Jong Gil, 55.

The trial at Shah Alam High Court in the outskirts of Kuala Lumpur, which began Oct. 2, entered its 29th day on Friday. A total of 34 witnesses have testified so far, mostly police and government chemists and forensic experts.

There remain only one or two witnesses left to take the stand before the judge rules either to call for the defense or to acquit the women.

The prosecution's case is built around footage from the airport security camera that captured the attack, the movement of the six accused and chemical evidence that confirmed the presence of the highly lethal VX nerve agent on the deceased and the two women.

Thus far what has been established in court was that Aisyah was recruited by another North Korean named Ri Ji U, 30, who introduced himself as a Japanese named James. They met on Jan. 5 last year at the Pavillion, a swanky shopping mall in downtown Kuala Lumpur.

Aisyah's lawyer Gooi Soon Seng said she was offered opportunities to act on what was claimed to be a Japanese YouTube prank show.

There she performed her first "pranks" whereby she swiped people's faces with a substance given by Ri Ji U. For her first "performance," she was paid 400 ringgit (about $101).

Over the next four days, Ri Ji U took her to perform "pranks" at KLIA and around Kuala Lumpur. Each time, she was paid 600 ringgit plus 50 ringgit for her taxi fare.

The police found photos of Ri Ji U on Aisyah's handphone that was taken at KLIA and outside the iconic Petronas Twin Towers.

They also retrieved records of text messages between the two from her phone.

Among the messages produced in court was one where after a "prank" on Jan. 15 last year outside Petronas Twin Towers, Aisyah texted Ri Ji U in her broken English, "I see today I acting no good, right?." James, whom she listed in her phone as "Jepun" or "Japan" in the Malay language, replied, "Not natural."

The key witness, investigating officer Wan Azirul Nizam, had testified that Ri Ji U left the country but he did not know when or to where. Ri Ji U was never caught and questioned by the authorities and Azirul said he was not at the airport on Feb. 13 when Kim Jong Nam was killed.

Huong, meanwhile, was seen walking with Ri Ji Hyon alias "Mr Y." In other footage, both Hong and Ri Ji Hyon were seen together with Ri Jae Nam or "Hanamori." Ri Jae Nam was also seen with O Jong Gil.

Azirul said Hong applied the VX liquid on Aisyah's palm and Ri Ji Hyon did the same to Huong's. Ri Jae Nam was described as the "mastermind" behind the assassination.

All four North Koreans later changed their clothes before flying out of Malaysia on the same day via KLIA's main terminal.

Other North Korean actors in the plot included Ri Jong Chol, who was the owner of a black van used to ferry Hong, Ri Ji Hyon and Ri Jae Nam to the budget terminal; Kim Uk Il, employee of North Korean airline Air Koryo, and Hyon Kwang Song, the second secretary of the North Korean Embassy in Kuala Lumpur.

According to Azirul, Ri Jong Chol, a chemist and computer expert, had told the police that an embassy official had in October 2016 approached him with a request that his name be used to buy the van.

"A few people from the North Korean Embassy" were with him when they went to buy the van and he claimed he never used it. Instead, he was driving a Peugeot with a diplomatic number plate from October 2015 to the day he was arrested on Feb. 17 last year.

Ri Jong Chol was deported on March 3 after being detained for two weeks due to insufficient evidence to press charges. Azirul said they failed to identify the man who drove the van on Feb. 13.

Kim Uk Il and Hyon Kwang Song, meanwhile, had been captured on camera helping his four compatriots to check in and board their flights out of the country. All four took a convoluted route to return to Pyongyang.

Kim Uk Il and Hyon Kwang Song were declared suspects by the police but they sought refuge in the embassy. The stand-off with the police lasted for weeks.

Kim Jong Nam's murder had spiraled into a diplomatic spat between Malaysia and North Korea that saw nine Malaysians at Malaysia's embassy in Pyongyang barred from leaving the country until Malaysia allowed Kim Jong Nam's remains and the two men holed up in the embassy to return to Pyongyang on March 30.

Before Kim Uk Il and Hyon Kwang Song departed Malaysia, police were given access to question the duo. Azirul told the court they claimed it was routine for them to send off their compatriots at the airport.

Without a single North Korean in the hands of the authorities, motive can only be implied as thus far prosecution has yet to establish one.

"The prosecution has not revealed any motive for the killing. This is more a case of political assassination," Gooi said outside court.

The court heard that Kim Jong Nam met with a Korean-American in Malaysia's northern island resort of Langkawi just days before he was murdered. Data from his laptop was copied onto a pen drive that was not among items found on the deceased.

This sparked speculation that he may have sold sensitive information on the North Korean regime to the American agent since some $138,000 was found in Kim's backpack and this could have brought his early demise.

Azirul, however, denied the speculation. He said police could not identify the American.

Chief prosecutor Muhamad Iskandar Ahmad told reporters recently that motive "is not an ingredient in a murder case," indicating that he only needs to prove the women had the intention to kill by their conduct.

"We only need to prove that both accuseds are at the same place i.e. the crime scene. They have the chance to attack the victim. The act was captured by CCTV. Victim said he was attacked. We have proven VX was used and VX and its precursor were found on the clothing of the two accuseds," Iskandar said.

"We managed to prove the four still at large, do exist but unfortunately had flown out on the very same day," he added.

Huong's lawyer Hisyam Teh Poh Teik said his client has "no knowledge" that the liquid applied on her was VX and she has "no intention" to kill.

"We are still very confident. We believe in our client. The actual culprits are the four North Koreans, not the two girls," Hisyam said.