CHICAGO -- The shooters in last week's California shootings traveled through Chicago last year.
A picture shows Tasfeen Malik and Syed Farook at customs at Chicago's O’Hare International Airport in July of 2014.
The FBI says both had been radicalized for some time, but they didn't say when or how.
Both shooters also took target practice days before they shot and killed 14 people in San Bernardino.
Investigators say they also had 19-pipes in their home, which could have been used to make bombs.