Policeman Killed in Central Paris

Days before the French presidential election, one policeman has been killed in a shooting in central Paris. The gunman is reported to have been shot dead. Also: mass protests in Venezuela, and the secret survival tactics of the naked mole-rat.

(Photo: Police officers block the access to the Champs Elysees in Paris after a shooting on April 20, 2017. Credit: THOMAS SAMSON/AFP/Getty Images)