THERE was nothing particularly remarkable about the two teenage boys who sat in the dock at Leeds Crown Court to hear all the evidence against them.

There were moments during the trial which lulled you into thinking you were hearing details of a typical teenager’s life; the older boy’s heartfelt diary entries, messages containing declarations of love, moments of friendship, of feeling like an outsider and being misunderstood.

But they would always be followed by sentiments which were disturbing in the extreme. The older teenager’s obsession was with a murderer – Eric Harris – and he dreamed of how he could carry out his own mass killing.​

These were children looking in some very dark places, pushing at doors that were open to them, accessing videos and websites on school shootings, Nazism, bomb-making, real-life deaths and other extreme content merely by searching Google.

When that wasn’t enough, they then turned their attention to navigating the internet’s darker waters and began accessing the deep web, where guns, drugs and other criminality thrives.

The older teenager was specifically looking for guns on the dark web and had ticked off “guns” and “amo” on a shopping list he had drawn up in his diary.

A run-down of the older boy’s internet search history put together by the North East Counter Terrorism Unit showed from the first incident of uploading a video glorifying the Columbine killers to his YouTube account in March last year, the teen rapidly descended into a spiral of viewing ever-more depraved and violent content.

By March 31 he had gone from reading about Columbine on the internet to researching Nazism, the SS and Gestapo. By the beginning of April, he was looking for balaclavas. By May he had been excluded from school for setting up a disturbing fake Instagram account, in which he targeted teachers at his school.

In the run up to his arrest in October, he sought out videos mocking the holocaust, real-life deaths and real-time suicides and obsessively read up on the Columbine shooters Eric Harris and Dylan Klebold.

The court heard from a friend of the teenager, whose testimony was at times profound in its incisiveness and way beyond her years.

She said he admired the killer Harris in particular because he was “openly angry” and homicidal, unlike his suicidal counterpart Klebold. He said Harris had introduced the idea of "not just hating yourself but hating everyone else and blaming them for how you feel".

She said he would use his Instagram account to post live suicides and pictures of “shooters” who had murdered people and would send distressing images to people he didn’t like, explaining: "It made people scared of him and he liked that. It made him feel powerful and worth something."

In between descriptions of the boys’ intense research into making explosives and incendiaries and accessing extreme content, there were moments when you were reminded they were children.

The court was read out messages sent by the younger boy one day in September, in which he wrote a list of names of people they intended to kill at school. The following day he messaged his mother, asking if she would buy him a leather trench coat.

“Do you think you’re out of the Matrix?” she joked with him and asked if he would be wearing shades with the coat.

“No. Combat trousers,” was the reply.

One of the younger teen’s accounts to police described how he felt he had been manipulated into some of the behaviour by his slightly older friend. 

While action was eventually taken to stop the boys going any further down their dark road, thoughts will now turn to why the authorities did not intervene sooner, and what more professionals could have done to recognise where they were heading.