Police have released CCTV footage showing a hospital patient moments before and after he set a fire inside a hospital.
John Watson can be seen entering an MRI room in this video before smoke fills the corridors and fire alarms were triggered.
Watson was jailed on Monday, 3 April, for causing £1.9 million worth of damage in the A&E ward at Lincoln County Hospital.
The fire was started on 29 March of last year.