How Reuters confirmed an Assad-era plot to move a mass grave

Working with a team of forensic geologists, a Reuters investigation drew on thousands of drone photographs and used comparative soil techniques to further corroborate a key finding: Former Syrian President Bashar al-Assad’s government transferred thousands of bodies from a known mass grave in the Damascus suburb of Qutayfah to a hidden location in the country's desert. This video contains content that some may find distressing. Jillian Kitchener reports.