Brussels terrorism
The singer was slated to perform in the Belgian capital on Sunday.
A radicalization expert explains what countries can do to stem the violence.
The arrests come two days after the attacks that killed at least 31.
The security lapses in a country that is home to the European Union and NATO have drawn international criticism.
WHAT'S HAPPENING
"Slogans aren't a strategy."
The city's mayor says it will take time to identify all of the attack victims.
His polling numbers rose after the Paris and San Bernardino attacks, but so did Ted Cruz’s.
Vigils and memorials were held across the world, honoring victims of the terrorist attacks.
Alphonse Lyoura pulled six or seven wounded people to safety.