When she returned to the FedEx with police, they recovered her phone and 68 others packed inside two boxes, Hannah said.
Most of the phones were put in airplane mode or had the SIM cards removed and taped to the back, according to police.
Authorities are now working to return the phones to their owners and identify and charge those behind the thefts.
The charges could range from theft by receiving to robbery, Hannah said.
"We are asking for anyone who believes they may have lost, misplaced or had a phone stolen during this festival to contact the lead Detective S.N. Krieger at firstname.lastname@example.org," Hannah said in the release. "Be prepared to provide a detailed description of their device and some evidence of ownership."
Shaky Beats drew thousands to Centennial Olympic Park for three days of electronic dance music and hip-hop. Zedd and Ludacris were among the headliners.
MORE: Shaky Beats 2018 lineup: Kygo, Marshmello, Zedd and more
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