One of the <a href="https://www.thenationalnews.com/gulf-news/saudi-arabia/2022/05/16/conjoined-twins-separated-a-year-after-arriving-in-saudi-arabia-from-yemen/" target="_blank">conjoined twins from war-torn Yemen</a> has died after a complicated 15-hour operation in Saudi Arabia to separate him from his brother. On Monday, the surgical team said one of the twins died as a result of a drastic drop in blood circulation and cardiac arrest. The <a href="https://www.thenationalnews.com/gulf/saudi-arabia/saudi-arabia-yemeni-conjoined-twins-moved-to-state-of-the-art-hospital-for-separation-1.1206640" target="_blank">19-month-old baby boys, Yusuf and Yassin,</a> were "conjoined in several organs". Twenty-four doctors were involved in the operation at the King Abdullah Specialist Children's Hospital in King Abdulaziz Medical City, Riyadh, the official Saudi Press Agency said. Doctors "faced great difficulties and challenges during the separation process, which made the deceased's condition critical after the operation", the SPA report said, adding that the surviving twin was in a stable condition. He is still being closely monitored in the ICU unit. Saudi Arabia's state-run King Salman Humanitarian Aid and Relief Centre regularly touts its humanitarian assistance to Yemen as evidence of Riyadh's commitment to alleviating the suffering there. The centre's doctors carried out the "four-phase surgery" separating Yussef and Yassin, describing it as "among the most complicated" they had performed, the SPA said. Last July, Saudi doctors separated a Yemeni baby from her twin, saying it was their 50th successful operation on conjoined twins. In December, Yemeni twins were separated by doctors in Jordan's capital Amman, before being flown back to Sanaa, according to the UN children's agency. Last week, Saudi King Salman ordered that another set of Yemeni conjoined twins, girls named Mawaddah and Rahmah, be transferred to Riyadh "to conduct medical examinations and check on the possibility" of separation, the SPA reported.