Influential Rangers fan group the Union Bears slammed Spanish police and security at the Ramon Sanchez-Pizjuan for treating football fans with "contempt."
And they claim it derailed their plans for a tifo during the Europa League Final.
Rangers took on Eintracht Frankfurt in Spain and the German side's supporters unveiled a huge display appearing to show the grim reaper praying with the Frankfurt badge clutched to his chest.
However there was no such display in the Rangers end and the Union Bears insist that was no fault of their own.
In a lengthy statement, they say they had arranged with stadium security to take a tifo to the game but were denied entry at the last minute.
And they've slammed the "overzealous" approach taken by police and staff at the stadium.
It reads: "The Union Bears would like to clarify and inform supporters as to why there was no tifo for the Europa League Final in Seville.
"Plans had been put in place, many man hours went into creating a tifo with over 5000 flags handmade between the semi final second leg and having to leave for the final. To get the materials to Spain our members drove for 27 hours each way.
“All materials had been authorised in advanced and access had been agreed, we thought it was all in hand, liaising with Rangers who then took the information to UEFA and stadium security.
"Pictures, measurements, material specification and details of when we could arrive at the stadium were all sent days in advance to Spain.
"However, on arrival, we were told that the stadium security denied entry to some of the flags we had prepared as they were on bamboo canes, which is the regular type of stick you would find a flag on at matches.
"Spanish police checked over the materials and insisted the bamboo canes could be used as 'weapons.' With the Spanish police now backing the security's decision, it essentially forced our hand to pull the display.
"The sizes and types of these canes were known to all, well before we set off for Spain. The decision to refuse the agreed tifo at the last minute is dumbfounding and lacks any sort of substance.
"While disappointed, we are not surprised by either the Spanish police or the stadium security's overzealous approach, or their clear contempt for football fans."
