Gary Guckenberger, 68, was shot by Seminole County deputies and confirmed dead on Wednesday after pointing a gun at deputies following child pornography allegations.
Sheriff Dennis Lemma said the investigation started a week ago after a tip.
A warrant was issued last Tuesday for Guckenberger's residence, where four cell phones and two computers were seized.
After obtaining devices, deputies found over 100 sexually explicit videos and 200 photos involving children from 3 to 9 years old.
While deputies were conducting surveillance on Wednesday, Guckenberger, a retired Seminole County firefighter, walked out with his walker, Lemma said.
Deputies tried to apprehend him. That's when he pulled a 38 revolver out of his waistband and raised it up.
A deputy said, "Don't do it." Guckenberger r