The FBI is asking for the public's help nabbing a robber holding up Valley banks by threatening them with bombs.
Agents have dubbed the man the "Dynomite" bandit because of how he uses explosive looking devices to rob the banks.
Phoenix FBI officials say the man robbed a Chase Bank in Peoria on July 3, a Wells Fargo Bank in Anthem on Dec. 21 and another Chase branch in Scottsdale on Wednesday.
FBI agents are investigating whether this latest string of robberies is connected to other cases.
Officials say on the day of the robbery, he doesn't even enter the bank. The night before he strikes, he cuts a hole in the roof of the bank and then plants a fake bomb.
The next day he calls bank workers and threatens to blow them up if they don't meet his money demands.
"His method of operation is usually to call the banks to ask for money, and that it be placed at a certain location. Obviously, he had to be somewhere in the proximity to collect that," said said FBI Special Agent Mark Hoffman.
So far, all of the bombs have been fake, but FBI agents say they're so detailed, they fool even the bomb squads.
"The same way he conducts his extensive surveillance and planning, he used that knowledge as well in his explosive devices. They look very realistic, they are inert, there are no explosive parts in it. But when you look at it, even the bomb tech professionals they look at it and believe it's an actual explosive device," said Hoffman.
FBI agents say his extensive surveillance, planning and detailed looking bombs lead them to believe he may have a military or police background.
There is a $15,000 reward being offered for information leading to his arrest.