The sentencing judge said Mohammad Farooq, 29, had been inspired by Islamic State and was radicalised online.

Farooq was found guilty last July of preparing acts of terrorism following a trial at Sheffield Crown Court. He had pleaded guilty before trial to possessing an explosive substance with intent to endanger life and other offences after being arrested outside St James’s Hospital in Leeds in January 2023.

Farooq was caught by police at the hospital, where he had previously worked as a student nurse, with a homemade bomb containing nearly 10kg of explosives extracted from fireworks.

Judge Bobbie Cheema-Grubb said Farooq had originally targeted RAF Menwith Hill, a Royal Air Force base in North Yorkshire which is also used by US forces.

“But having realised it would be impossible to get into a position to detonate your device anywhere closer than the well-protected perimeter, you changed tack to a softer target,” she said.

Farooq was jailed for a minimum of 37 years in prison before he can be considered for parole.

“Farooq came dangerously close to harming innocent people,” counter terrorism police superintendent Paul Greenwood said.