Another terror attack on a major European city. This time it's Vienna, where a suspected islamist extremist opened fire. It's a city Katya Adler knows well - she joins Adam and Frank Gardner to discuss the apparent rise in these incidents, and the challenges facing Europe's leaders in deciding how to respond.

Liverpool is to be the test case for mass testing - Mayor Joe Anderson explains how it's going to work, while Adam and Fergus pore through the new lockdown restrictions, hot off the press - and attempt to answer your questions about how they'll work.

Studio director: Emma Crowe