The Syrian refugee crisis just got worse, due to the Paris attacks. What made it worse? Sunday's revelation that at least one of the Paris terrorists who killed more than 120 people on Friday entered Europe as just another face in the crowd -- embedded in the current wave of Syrian war refugees. The development appears likely to fire up the security debate over what to do with them. One of the men who attacked Paris held an emergency passport or similar document, according to an unnamed French senator who was briefed by the French Ministry of the Interior. The senator told CNN the bomber falsely declared himself to be a Syrian named Ahmad al Muhammad, born on September 10, 1990, and was allowed to enter Greece on October 3. From there he moved to Macedonia, then Serbia and Croatia, where he registered in the Opatovac refugee camp, the lawmaker said. Eventually, he made his way to Paris, where he was one of three men who blew themselves up at the Stade de France. So far, Germany has been the most welcoming country, saying it might take in 1 million migrants by the end of the year. "Paris changes everything," Bavarian finance minister Markus Söder told Die Welt am Sonntag. "It cannot be that we don't know who is coming to Germany and what these people are doing here. This situation must be brought to an end by any means," said Söder, echoing comments by state premier Horst Seehofer.