US Secretary of Defense Pete Hegseth has said an American submarine sank an Iranian warship in the Indian Ocean.Washington says it's the first time since the Second World War it's used a torpedo to sink an enemy vessel.Also on the programme: we gauge the scale of the attacks inside Iran by speaking to a resident in Tehran and verifying video footage; and a look at a new AI model, trained on the DNA of over 100,000 species, that is capable of designing new genomes.(Photo: US Defence Secretary Pete Hegseth speaks during a press briefing at the Pentagon on 2 March. Credit: EPA/Shutterstock)