Police believe Loibl -- who is from St Petersburg, Florida -- traveled to Grimmie's concert in Orlando Friday night specifically to shoot her.
He allegedly arrived armed with two handguns and a hunting knife, reported Entertainment Weekly.
Loibl allegedly opened fire on Grimmie during a meet and greet with The Voicealum after the show. Her brother, Marcus, tackled Loibl to the ground, and Loibl then allegedly killed himself.
Police say Grimmie died from her gunshot wounds.
Police said in a press conference that he likely was a deranged fan.
"That would be speculation, but that's what it's looking like," said Orlando police chief John Mina.
"There's no indication that he knew her, we're looking into that to try and find a motive for the crime."
Mina said they were looking into his phone and computer for further information.
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