When they left, it emerged that some seats had been defaced with the number 66.

That was the number of deaths resulting from a crush among the crowd at a Rangers v Celtic game in 1971.

There were also photographs of stairway 13, where the disaster occurred, stuck on the seats, with the images accompanied by the words: "Stairwell Thirteen - it's the greatest sight that I have ever seen."

Graffiti also mocked the death of Queen Elizabeth II and supported the IRA.

A Rangers spokesperson said: "Rangers condemns in the strongest possible terms the graffiti and stickers left by a section of the Hibernian supporters at Ibrox this afternoon.

"The Ibrox disaster remains the darkest day in our club's history and continues to affect a number of families to this day. The mocking and celebration of such an event is outrageous and has no place in any football stadium or society as a whole."

Rangers said they would be working with the Edinburgh club to identify those responsible, while Hibs have asked anyone with information to contact their website.

A Hibernian spokesperson said: "Hibernian FC is aware of the intolerable graffiti and stickers found in the away end at Ibrox today and condemns the behaviour of the individuals that were involved.

"The club will work with Rangers to identify those responsible and will take the most serious action possible against anyone involved."