Police officers stand in front of demonstrators in front of the Maritim Hotel in Cologne, western Germany, to block a protest against the party congress of Germany's right-wing populist Alternative for Germany (AfD) on April 22, 2017. The anti-immigration party, which hopes to win its first seats in the national parliament in a general election in September, will gather in the western city of Cologne on April 22-23, 2017. / AFP PHOTO / Odd ANDERSEN