KUALA LUMPUR (Reuters) - A lawyer for one of two women accused of killing the estranged half-brother of North Korea’s leader said on Friday he was seeking the help of foreign experts to assess the evidence related to the alleged murder weapon - VX nerve agent.

Indonesian Siti Aishah, 25, and Doan Thi Huong, 28, from Vietnam, have been charged with murdering Kim Jong Nam at Kuala Lumpur airport on Feb. 13 by smearing his face with VX, a chemical the United Nations describes as a weapon of mass destruction.

They face the death penalty if convicted.

Malaysian prosecutors have handed defense lawyers 44 documents including toxicology, autopsy, arrest reports, the suspects’ statements and photographs, the lawyers told a hearing on Friday.

Gooi Soong Seng, Aishah’s lawyer, said some of the documents would be sent to experts in Denmark and other countries to get assessments on the alleged use of VX agent.”In the post-mortem ... they have confirmed that the cause of death was by VX. So we will be looking thoroughly at the VX aspect,” Gooi told reporters.

He did not elaborate on what particular aspect he wanted the experts to look into.

U.S. and South Korean officials say the North Korean regime was behind the murder of Kim Jong Nam, who had been living in exile in Macau and had criticized his family’s dynastic rule of North Korea in the past.

Kim was the eldest son of the late North Korean leader Kim Jong Il. His half brother, Kim Jong Un, became North Korean leader when their father died in 2011.

North Korea has refused to accept the dead man was leader Kim Jong Un’s half brother, and has suggested the victim died of a heart attack. It has accused Malaysia of working with South Korea and other “hostile forces”.

Aishah and Huong have told diplomats from their countries that they believed they had been taking part in a reality television show prank when they assaulted Kim Jong Nam at the airport.

Gooi said the defense was still awaiting CCTV recordings of the murder, and of “video pranks” that the women had allegedly carried out at hotels and shopping malls around Kuala Lumpur.

Hisyam Teh Poh Teik, Huong’s lawyer, said the defense was also looking for “essential evidence” in Vietnam, but declined to elaborate.