The man police say opened fire yesterday outside the Empire State Building bought the gun he used legally in Sarasota, Fla., more than 20 years ago.
He illegally brought the gun, purchased in 1991, to New York City, ABC News reported Friday.
Johnson began shooting outside the Empire State Building Friday morning during rush hour.
Nine were injured in the subsequent shootout between Johnson and police.
Both Johnson and his intended target Steven Ercolino were killed.
A witness told ABC News Johnson approached Ercolino carrying a black bag.
"She saw him walk up to Ercolino and without saying a word, fire five times at the victim and keep firing as Ercolino slumped to the ground," ABC News reported.
Here are pictures of the chaos around the Empire State Building. Warning, some are graphic >
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