Image caption Moffat's comments were prompted by internet postings by Doctor Who fans

Doctor Who chief writer Steven Moffat has attacked fans of the show who reveal crucial plot lines ahead of transmission.

"You can imagine how much I hate them," he told BBC Radio 5 live. "It's only fans who do this, or they call themselves fans.

"I wish they could go and be fans of something else."

Before the current series began, a fan posted the entire plot of the first two episodes on an internet forum.

They were among a number of fans who were invited to a press screening, at which the production team asked people not to give away spoilers.

"It's heartbreaking in a way because you're trying to tell stories, and stories depend on surprise," said Moffat.

"So to have some twit who came to a press launch, write up a story in the worst, most ham-fisted English you can imagine, and put it on the internet [is heartbreaking].

Media playback is unsupported on your device Media caption Why Steven Moffat is angry with the Doctor Who fans who spoiled the plot

"I just hope that guy never watched my show again, because that's a horrific thing to do."

He said the majority of Doctor Who fans were "spoiler-phobes" who refused to go online for fear of finding out any information in advance.

"They want to preserve the surprise," he said. "The tragedy is you have to work hard at that now."

Moffat said he believed that keeping elements of storylines under wraps was an essential element in drama.

"Stories depend on shocking people," he said.

"Stories are the moments that you didn't see coming, that are what live in you and burn in you forever.

"If you are denied those, it's vandalism."

The current series of Doctor Who continues on BBC One on Saturday.