Having declared “war” on the organisers of England’s Reading and Leeds festivals, where the act was late on stage and claimed it had a special dispensation to break the curfew, the U.S. rockers’ late appearance at O2 Arena was greeted with an aerial bombardment of plastic bottles containing an “unknown substance.” The unknown substance was widely reported to be urine.

“Here’s the deal: One more bottle and we go home,” frontman Axl Rose warned the audience when the aerial battery became too much. Soon another bottle landed and the group left the stage.

Having taken an hour to get the act on stage, MCD chief Denis Desmond and the O2 staff were forced to take another hour to persuade it to return. Desmond himself went on stage to appeal for calm after a member of the venue staff announced the show would go on when some “technical difficulties” had been sorted.

The band was eventually forced back on stage to a depleted crowd and didn’t stop playing until nearly 1 a.m. MCD said the artist was “prevented from leaving the venue by the promoter” until it completed its set.

Irish senator Michael McCarthy complained of reports saying the lights came back on and fans were told to go home, which meant they missed seeing the whole show. Desmond has since told Pollstar that at least three-fourths of the crowd stayed and any that left were probably reliant on public transport to get home.

Michael Kilcoyne of the Consumers Association of Ireland also claimed that some form of compensation was required. He said consumers bought a ticket to the concert on the basis that the lead singer would be on time and would not walk off in the middle of the show.

“Consumers were inconvenienced by what happened and they are entitled to some sort of credit from MCD or a half refund of their ticket,” he said.

MCD has since issued a statement saying the band played its full set of songs and the “issue of refunds does not arise.” It also said, “While the artist has a long history for being late on stage, no artist should be subjected to missiles and unknown substances being thrown at them.”

The National Consumer Agency, the statutory body that defends consumer interests in the Republic of Ireland, has been called to pressure MCD into paying some form of compensation. But the NCA isn’t having anything to with it. It says the only route open to disgruntled fans seeking redress is to fight the issue with MCD in small claims courts.

The number of claimants will likely be determined by whether Guns N’ Roses fans think the band or the promoter was responsible for the Dublin fiasco.

Melvin Benn from Festival Republic, the Leeds and Reading festival promoter that’s co-owned by Desmond and Live Nation, played down the U.S. rock acts’ declaration of “war” against his firm after it headlined the twinned events at the end of August.

At Reading, Rose had delivered an expletive-ridden tirade against police and organisers as he left the stage.

“I’d definitely book them again but I don’t know if they’d come and play,” Benn told New Musical Express, acknowledging that he also doubted if he’d “be getting a Christmas card from them.” Reading organisers turned off the power because the act’s late appearance caused it to overrun the curfew.

“There are rules we have to abide by here in the UK; they’re very clear rules. It’s not personal. I think the band is great. Why would I make it personal?,” he explained.

As of Sept. 6, Guns N’ Roses’ European tour was to visit a further 20 cities across 12 countries.