A "lone wolf terrorist who had become radicalized" and brought a device to his place of employment with the intention of "killing as many nurses as possible" has been found guilty of planning terrorist activities.

The Boston Marathon terrorists in 2013 utilized pressure cooker bombs, which were intended to be twice as destructive. Mohammad Farooq, 28, was apprehended at St. James's Hospital in Leeds.

Sheffield Crown Court heard Farooq had immersed himself in an “extremist Islamic ideology” and went to the hospital to “seek his own martyrdom” through a “murderous terrorist attack”.

Prosecutors said Farooq had originally intended to attack RAF Menwith Hill – a North Yorkshire military base used by the United States that had been identified as a target by so-called Islamic State.

When he thought that was not possible, jurors were told Farooq then switched to the “softer and less well-protected target” of St James’s Hospital in the early hours of January 20 last year.

The defendant was a clinical support worker at the hospital and his “secondary motive” for choosing it was that he had a grievance against several of his former colleagues and had been conducting a poison pen campaign against them, the court heard.

Farooq denied preparing terrorist acts, with defence counsel Gul Nawaz Hussain KC telling jurors Farooq was not an extremist but a “troubled man” who was motivated by “deep rooted anger and grievance” towards his colleagues.

On Tuesday a jury convicted him of the offence after deliberating for less than two hours.

Opening the case to jurors in June, prosecutor Jonathan Sandiford KC said Farooq’s plan was to detonate the bomb, then kill as many people as possible with knives before using an imitation firearm to incite police to shoot him dead.

The first was that a bomb threat he sent in a text to an off-duty nurse in order to lure people to the car park where he was waiting was not seen for almost an hour, and the full-scale evacuation he had hoped for did not happen.

The prosecutor said Farooq left but returned shortly afterwards with a new plan to wait in a hospital cafe for a staff shift change and detonate his device.

But Mr Sandiford told the court that “luck intervened again” because a patient, Nathan Newby, was standing outside the hospital having a cigarette and “noticed the defendant”.

He said: “Mr Newby realised something was amiss and began to talk to him instead of walking away.

“That simple act of kindness almost certainly saved many lives that night because, as the defendant was later to tell the police officers who arrested him, Mr Newby succeeded in ‘talking him down’.”

Mr Sandiford said Farooq told Mr Newby about his grievances towards his colleagues and his plan to take the bomb into the hospital and “kill as many nurses as possible”.

Mr Newby stayed with the defendant and eventually persuaded him to move away from the building, and hand over his phone to call the police.

Officers who arrested Farooq found the “viable” pressure cooker bomb had just under 10 kilograms of low explosive. He also had, with him or in his car, two knives, black tape and a blank firing, imitation firearm.

An investigation found he had become self-radicalised through accessing extremist material online, and had obtained bomb-making instructions in a magazine published by Al Qaeda to encourage lone wolf terrorist attacks against the West.

Movements of Farooq’s mobile phone and car showed he made at least two visits to the area of Menwith Hill in the 10 days leading up to his arrest, jurors were told.

Mr Sandiford said the base had been designated as a target by IS because it was believed it had been used to co-ordinate drone strikes against terrorists.

Farooq admitted firearms offences, possessing an explosive substance with intent and having a document likely to be useful to a person preparing or committing an act of terrorism.

Bethan David, head of the CPS Counter Terrorism Division, said: “Farooq is an extremely dangerous individual who amassed a significant amount of practical and theoretical information that enabled him to produce a viable explosive device.

“He then took that homemade explosive device to a hospital where he worked with the intention to cause serious harm. Examination of his electronic devices revealed a hatred towards his colleagues at work and those he considered non-believers.

“It is clear from his internet searches that he was also conducting extensive research of RAF Menwith Hill, with a view to launching a potential attack.

“The extremist views Farooq holds are a threat to our society, and I am pleased the jury found him guilty of his crimes.”