German Terrorism Case Highlights Europe’s Security Challenges

BERLIN — The warning came to the German security authorities in early September from “our best partners,” as they euphemistically refer to the American intelligence agencies: A terrorist assault might be in the works.

In the weeks that followed, the Germans identified a suspect, a refugee from Syria. They unearthed evidence that he had been casing a Berlin airport for an attack, and they recovered powerful explosives from his apartment, only to see him slip through their fingers. When they eventually captured him, the suspect promptly hanged himself in his jail cell.