New information about the Oct. 1 Las Vegas shooting carried out by Stephen Paddock was unveiled on Friday
The agent says in the October 3 document that there was no evidence at that time of "criminal involvement" by Danley, but that investigators had not ruled out the possibility.
Paddock is suspected of killing 58 people and injuring hundreds attending the Route 91 Harvest festival in Las Vegas on October 1 before taking his own life.
Stephen Paddock's emails were disclosed in affidavits unsealed Friday after several media organizations, including The Associated Press, fought for their release.
Paddock wrote back that he wanted to try several scopes and different types of ammunition.
A third read: "For a thrill try out bump fire ar's with 100 round magazine".
A USA judge in Nevada unsealed documents Friday showing some of what federal agents learned about Stephen Paddock in the week after the Las Vegas shooting. "Located in the las vegas area", read one message sent to an account investigators believe was controlled by Paddock, the documents state.
An FBI special agent wrote in one affidavit seeking a search warrant that "the methodical nature of the planning employed by Paddock, coupled with his efforts to undermine the preceding investigation, are factors indicative of a level of sophistication which is commonly found in mass casualty events such as this".
Investigators at the time of the filing had been unable to determine if Paddock was sending emails between two accounts both belonging to himself, or was communicating with someone else.
The documents also showed that Paddock's girlfriend, Marilou Danley, told investigators before they searched a house that the two shared that they might find her fingerprints on ammunition "because she occasionally participated in loading magazines", the Review-Journal reported.
Paddock's email address and the Gmail address had similar names, leading investigators to suspect that he may have been emailing himself, although they couldn't figure out why.
The FBI document, filed six days after the shooting, says authorities had no evidence suggesting Danley had any criminal involvement in the massacre. If another person was involved in the incident, "investigators need to determine who was communicating with him about weapons that were used in the attack", one Federal Bureau of Investigation agent shared with CNN.
Danely's attorney did not respond to a call or text seeking comment on Friday evening. Investigators were only able to search one but could not unlock the others.
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