Policemen stand guard in front of a team bus of French football club AS Monaco at the team's hotel in Dortmund, western Germany, on April 12, 2017, prior to the UEFA Champions League quarter-final, first-leg football match of German first division Bundesliga club Borussia Dortmund vs Monaco, and one day after an attack on Dortmund's team bus.
German investigators detained an Islamist suspect over three explosions that rocked Borussia Dortmund's team bus, prosecutors said, confirming that the probe was examining a possible "terrorist link". / AFP PHOTO / Sascha Schuermann        (Photo credit should read SASCHA SCHUERMANN/AFP/Getty Images)