Teenager said to have planned Columbine-type massacre told friends on Facebook he would be a martyr, Old Bailey trial hears

A teenager accused of planning a repeat of the Columbine massacre texted his friend to say he had a "strong urge to shoot" at a nursery as part of a terror plot, a court has heard.

Jurors in the trial of Michael Piggin, 18, were on Wednesday shown a series of videos, text messages and Facebook conversations allegedly showing "an escalation in the verbal and physical threat" from the teenager.

In one text message shown to the jury, Piggin, the prosecutor said, told a friend on 20 December 2012: "Can't believe I'm telling you this. After I picked up my pistol holster I was walking past a nursery. I felt a strong urge to shoot."

The court heard that Piggin's friend told him it was "just a mental thing", to which Piggin replied: "I nearly gave in but I fought it and I hit my mum. We had an argument, she said some mean stuff, I flipped."

The Old Bailey heard on Monday that Piggin, who has Asperger's syndrome, had drawn up a hit list that included his college, a local mosque, a cinema, Loughborough University and the town's council offices, as part of what he called Operation: The New Columbine.

Max Hill QC, prosecuting, told jurors on Monday that detectives had seized 11,000 Facebook conversations when Piggin was arrested in February 2013, including some in which he discussed "revenge" plans to "take out as many scumbags as possible".

Wearing jeans, a black T-shirt, spectacles and a dog tag, Piggin sat in the dock as his private chats were read to the court.

In one conversation 48 hours before his arrest in February 2013, Piggin told a friend he planned to carry out the attack in April, jurors heard. "Seems like I've been planning this forever," he said, discussing whether to send a suicide note to the media, the jurors were told.

"I'm gonna be a martyr," Piggin wrote in another Facebook message, the jury heard. "I'll be looked up to by other people like me."

In another message read to court, he said: "I want people to know the full story so I can inspire people. It's hard to carry on most of the time, then I think the longer I plan it the bigger it will be, more scum I will kill."

In text messages read to jurors Piggin appeared to express sympathy for the perpetrator of the Virginia Tech shooting in 2011. "Feel sorry for the guy who done it. His confession video is sad. I will show you it tomorrow if you want," he is said to have told a friend.

The court heard that Piggin wrote in another text: "When you get your new air rifle we will meet up and both bring rifles and go for a bit of a shooting session down the mosque."

Jurors were also shown home-made videos, including one in which Piggin throws a molotov cocktail at a wall, before saying: "Yes you bastards! Have that, you Muslims."

Hill told jurors that Piggin's amateur films were often haphazard and comical. In one video played to the jury, Piggin ranted about Islam in front of a Scottish flag pinned to the wall, before making rude gestures behind his friend's back as he addressed the camera.

"You will consider whether this young man, Michael Piggin, is a laughing stock, an adolescent incompetent or whether – despite the comical content of some of these films – there is an aspiration of something more, an intention to go on to something much more serious indeed," Hill said.

Piggin stockpiled a "striking" arsenal of weapons in his bedroom, the court heard, including nine partially assembled petrol bombs, air rifles, a gas mask, a crossbow, and a camouflage flak jacket.

In his bedroom the teenager had a Nazi swastika above his bed alongside a poster of the Batman character Joker from the film Dark Knight, as well as press cuttings about Anders Breivik, the Norwegian murderer who killed 77 people in 2012, the court heard.

Piggin denies two terror-related charges.

The trial continues.