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Twitter user @AntipodeanMs posted an image appearing to show an unfinished clock tower

Secret Cinema has scrapped a second immersive screening of Back to the Future, hours before it was due to begin in east London.

Organisers said they had "no choice but to cancel" the event after coming across a "number of issues we have not experienced previously".

They told ticketholders to "stand by" for details about Saturday's screening.

Fans were furious after Thursday's opening night was pulled with three hours' notice.

A preview screening on Wednesday was also cancelled.

Organisers said Thursday's show had been called off "due to unavoidable circumstances".

The company announced on Friday morning it had been "working urgently through the night to resolve the issues on site", but it appears their efforts have not been enough.

Although the company did not specify the details why the event was not going ahead, it suggested the issues it faced were unusual after "running safe arts events for 10 years".

"As you can imagine we are hugely disappointed and share the immense frustration," it said.

"The site is looking spectacular so please standby for further information about Saturday night's event."

It has offered ticketholders - who paid £53.50 each - the opportunity to another scheduled screening date instead, or a refund.

Ticketholders vented their frustration on social media at the cancellations and uncertainty over Saturday's screening.

"You shouldn't be working through the night when it started yesterday and you had months to prepare," Adrian Reynolds posted on Secret Cinema's Facebook page.

Simon Fish wrote: "What about tomorrow? I have a bus at 7:45 from Cardiff and I don't want to be on it if it's cancelled, don't want to travel to London for nothing so can you let us know now please."

Lucy Mans said: "I think I can speak for everyone who is booked for tomorrow when I say, that if you already know tomorrow is looking unlikely please warn us with more than little over an hours notice."

Andy Thomas added: "I've bought tickets for tomorrow on the pretence there'd be a few shows before it so any issues would have been ironed out.

"Right now, it looks like it's going to be the new opening night and will be an utter shambles as there's not been a dress rehearsal or two previous nights to iron out any kinks etc, so I've practically got no enthusiasm for this anymore as it's not what I bought into."

Earlier on Friday other people suggested the location for the screening - an ambitious recreation of Hill Valley, the town in which Back To The Future was set - remained unfinished.

One Twitter user posted a picture which appeared to show the replica clock tower without its clock.

With only a few hours before Thursday's show, Secret Cinema said it was "unable to receive guests" and it was "devastated" to announce the cancellation at such a late stage.

Up to 84,000 tickets were available for Secret Cinema's latest production - but audience members had been told to leave their phones at home, meaning many were unaware of Thursday's cancellation until they arrived to see the film.

Some had travelled great distances for the event.

"We have travelled from the Isle of Wight with our two young children," Rowan Middleton-Leal posted on Facebook, from a hotel room he had booked in order to attend the show.

"We literally came from Cambodia and won't be around for rescheduled tickets," added Matthew Bowen.

Great Scott!!

who would've played Marty McFly?  ???
...It is an screening of Back to the Future, so it will be Michael J. Fox.