The suspect is a doctor from Saudi Arabia, living in Germany since 2006. We hear from a local member of the state parliament and a counter-extremism expert in Berlin. Also on the programme: Both houses of the US Congress have voted in favour of a short-term spending bill to avert a government shutdown; and the wonders of swimming mice, dwarf squirrels, and blob-headed fish.

(Picture: Tino Chrupalla, co-leader of the Alternative for Germany party visits the site of the Christmas market attack in Magdeburg, Germany. Credit: Reuters/Christian Mang)