(WXYZ) - The chaotic scene in Washington D.C. reminds us all of the real life threats we still face.
It's something former FBI Special Agent in Charge Andy Arena is closely familiar with.
"You've got a mass casualty scene and a law enforcement response, you're trying to lock down that area and do door to door and building to building searches," said Arena. "You don't want to take the eye witness accounts at first glance, because different people see different things, so you have to weed through it and get the total picture."
For years, Andy Arena ran counter terrorism operations at FBI headquarters in Washington D.C.
He stresses the importance of maintaining good communication between the public and law enforcement as well as taking the time to conduct concise interviews to gage exactly what unfolded in a mass shooting.
"It's just utter chaos in these situations and if you get 10 witnesses...in a stressful situation they may see 10 different things," said Arena.
Lastly, establishing a possible link to terrorism can be crucial. If in fact the attack was motivated by someone looking to further a political or ideological agenda, the FBI could remain the lead agency for the duration of the case.
"This is a tricky one because it's a military base so if it's not a terrorism incident then it's run by NCIS, if it's terrorism then the FBI would," said Arena.
Arena says often times attacks turn out to be planned by a group of individuals. However, we've also seen the lone wolf scenario play out when someone acts alone.
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