DENVER – The Denver Broncos are warning fans to be wary of tickets bought from secondary markets and websites, as some fans are being left out of hundreds of dollars after buying counterfeits.

The team said Thursday that it has recently seen an uptick in the fake tickets, which have been printed both on Ticketmaster stock and sent in PDF form.

It is reminding fans that they buy tickets from unauthorized sites at their own risk, and that the only sure-fire way to get a legitimate ticket is to buy them at Ticketmaster, the NFL Ticket Exchange, at the Denver Broncos Box Office or at Broncos events.

The team says it is “working closely” with the Denver Police Department to investigate the counterfeiting schemes.

One person who bought $600 worth of tickets for the Oct. 1 Broncos-Raiders game from scalpers found out at the gate they were fakes, they told Denver7.

The Broncos confirmed to Denver7 that "several hundred" counterfeit tickets were created for that game.

After he filed a police report with DPD, the department worked with the Broncos and its security to secure the group new seats, but the Broncos say people buying from unauthorized sites do so at their own risk.

Denver7 has reached out to Ticketmaster for further comment, but the request were not immediately returned. DPD says the Broncos and its team are handling the counterfeit situations.

The Broncos ask anyone with questions about their tickets to contact the ticket office at 720-258-3333 or at tickets@broncos.nfl.net.