Jan. 13, 2016
ByDION NISSENBAUM and AYLA ALBAYRAK in Istanbul, and
Bomber was officially registered but didn’t set off security alerts
The Islamic State suicide bomber who killed 10 German tourists in the heart of Istanbul registered here as a Syrian refugee without setting off security alerts—even though his brother had blown himself up in Syria, Turkish officials said. The revelation highlighted concerns that extremists are using the migrant crisis to cross borders and carry out terrorist attacks.