GBI officials said in the past two and a half weeks, the agency has investigated four deadly officer-involved shootings that involved replica handguns.
The GBI said it is investigating cases out of Atlanta, Savannah, Dunwoody and Gwinnett County.
On Jan. 20, a robbery suspect, who allegedly had a BB gun, was shot and killed in a shopping center parking lot in Dunwoody.
Authorities say a murder suspect was pointing a BB gun at police and U.S. marshals in Savannah when he was shot and killed on Jan. 24.
Police said an armed man was shot and killed when he pointed an airsoft replica pistol at officers in Gwinnett County on Jan. 25.
Last week, an armed robbery suspect with a BB gun was shot and killed by officers in East Point.
"They're all open investigations," GBI spokesperson Nelly Miles said.
Channel 2's Mark Winne compared photos of the replica guns to real guns.
"The guns you showed me look identical to the real guns that I've seen in my 40 years of law enforcement. There's no way that in split-second you can tell whether they're real," said Moses Ector, a retired GBI official, retired police chief and current director of a police leadership academy.
Ector said he's known many officers who made the decision to pull the trigger.
"(They have to) live with it for the rest of their life," he said.
Ector said knowing the gun lookalikes turned out to not be firearms in these cases probably won't help the officers' mindsets moving forward.
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