An armored car guard fatally shot this week during a robbery as he refilled an ATM is the third guard in the Houston area who's been killed in the last 18 months.
The Houston Chronicle also reports that Monday's ambush at a Wells Fargo ATM in northwest Houston is the fifth attack this year.
Federal authorities say none of the cases have been solved.
Another armored car guard was killed in February 2015 and the third was fatally shot in March.
In Monday's ambush, the 25-year-old man who was killed was accompanied by another guard who remained in the vehicle. That second guard was not hurt in the shooting.
Authorities have described the suspects as "very aggressive."
Copyright AP - Associated Press
