Missing Titanic submersible search continues

US and Canadian coastguards continue the search for the Titan vessel that went missing on Sunday. We hear from Colonel Terry Virts, a friend of British billionaire Hamish Harding, one of the five people on board the missing vessel. We also hear from Professor Alistair Greig about the challenges of the rescue operation. Also on the programme: police in British Columbia say the killing of the President of the Sikh temple was a targeted killing; and glaciers are melting at an unprecedented rate across the Hindu Kush Himalayan mountain ranges. (Pic credit : Oceangate)