A team of doctors at the King Abdullah Specialist Children’s Hospital (KASCH) in Saudi Arabia’s capital Riyadh on Thursday, June 6, started a 7.5 hour surgery to separate a Filipino conjoined twins.

The 17-month-old twins— Akhizah and Ayeesha Yusoph— are conjoined at the lower chest and abdomen, sharing a liver.

They have a combined weight of 18 kilograms, each with a complete set of upper and lower limbs.

On May 5, the twins arrived with their mother and grandmother via a Saudi Ministry of Defense medical evacuation aircraft.