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Dougherty siblings may have planned crime spree, says ex-FBI agent

Dougherty siblings chase video released by police in Fla.
Ryan Edward Dougherty, Lee Grace Dougherty, Dylan Dougherty Stanley AP

(CBS/WTSP) - ST. PETERSBURG, Florida - At first glance, it may look like the Dougherty siblings - two brothers and their sister who have been on the run from Pasco County for a week - simply don't want to go back to jail.

Pictures: The Dougherty Siblings

But an expert told CBS affiliate WTSP the group may have had their escape planned for a while.

Brian Kensel is a retired FBI special agent, who worked for decades chasing fugitives and leading SWAT teams. He says the family of fugitives appear to be the most dangerous kind of criminals.

"The suspect that doesn't care if he or she lives or dies is the worst case scenario for a law enforcement officer," Kensel explained.

He says all signs point to that being the mindset of the Doughertys. Kensel also points out the family dynamic may make them even more of a threat.

"It's an 'I'll die for you, you're my brother, you're my sister' kind of a thing," he said.

The three took off one week ago Tuesday, accused of trying to kill a Zephyrhills police officer as he tried to pull them over, then robbing a Georgia bank a few hours later.

But Kensel thinks it may have been thought out long before that. He points detectives reportedly found a bunker underneath their home, and they're said to have a stockpile of weapons.

Plus, with their faces splashed on billboards all over the country and every cop looking for them, the three have managed to disappear.

"That certainly goes to a mindset that has existed for a period of time. This is certainly not a spur of the moment crime," Kensel said, "For some unknown reason, they decided to separate themselves from society."

If they are found and a standoff ensues, Kensel tells WTSP his negotations would start by trying to convince them their crimes up until this point, haven't been too serious.

"Nobody has gone to the hospital. Nobody has gone to the morgue. They've not been injured. I think that would be very appropriate to point out to them," Kensel explained.

He also mentioned the car the three were suspected of driving away in - even if they're no longer in it - hasn't been found anywhere. He says that's another sign it could have been planned. 

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August 9, 2011 - Dougherty siblings chase video released by police in Fla.
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