UN human rights investigators have said that the cycles of vengeance and reprisal must be brought to an end in Syria, as the country commemorates the first anniversary of the overthrow of Bashar al-Assad. A UN independent commission of inquiry commended the steps taken by Syria's new leadership to address the crimes and abuses of the Assad era. But it said violent incidents in the past year had raised worries about the future direction of the country. Newshour's Lyse Doucet is in Damascus.

Also in the programme: we profile Formula 1's new champion Lando Norris; and a new documentary looks at what senior US military officials know about UFOs.