A young arsonist has been sentenced to 17 months’ jail for setting fire to her then boyfriend’s flat.

But Deemster Montgomerie extended Lisa Nicola McGhee’s sentence for licence purposes to a maximum of three years and seven months, given the danger she posed.

He told her: ’Clearly, the consequences of your actions could have been much worse. I consider you pose a genuine danger to the public.’

The Court of General Gaol Delivery heard McGhee, 20, had committed the offence while still on probation for an earlier arson. She had admitted liking to see fires.

Prosecutor Rachael Braidwood said the fire service had responded to a 999 call to the Craig-a-Del flats on Marathon Road, Douglas, at about 12.20am on January 6 this year. The fire alarm sounded and one resident saw flames coming from flat 4 where McGhee’s boyfriend lived.

Armed with a fire extinguisher, the neighbour forced open the front door.

The bedroom door was closed, and when they looked inside they were faced with immediate heat and thick smoke.

The were 16 flats in the block and 13 people in the building at the time.

Firefighters dealt with the blaze which had started among clothes and other combustible materials in a cardboard box on the floor at the foot of the bed.

It had just started to spread as the emergency services arrived, the blaze having been restricted by lack of oxygen due to the fire door and windows being closed.

Damage was confined to the bed, carpet and wallpaper but the flat could not be rented out again for seven weeks.

When arrested at her home on Ashbourne Grove, Douglas, McGhee, who was 19 at the time, said she had been with her boyfriend and had just got back 10 minutes ago.

Her boyfriend told police that McGhee had been with him in the flat at all times until they went to go for a drive. She had told him she needed to go back inside to pick up her medicine tub.

She returned a short time later and said she wanted to go for a long drive and got upset when he told her he did not want to as it was already 12 midnight and he had college in the morning.

When he looked at his phone he noticed it had been put in airplane mode, which said he would never have done himself.

A fire service investigation estimated the blaze had started within 40 minutes of the 999 call.

A battery pack found on the floor in the bedroom was ruled out as the source of the blaze and no discarded cigarettes were found, making deliberate ignition the most likely cause.

The court heard that McGhee had been sentenced to a two-year probation order last November for an earlier arson at her then flat in Mona Street.

A neighbour had called 999 on May 26 last year after spotting flames under the door of flat 2.

McGhee admitted two counts of arson being reckless as to whether life would be endangered in relation to the January fire, one charge relating to damage to property and the other to damage to the building itself.

Sentencing her to 17 months’ custody, with her sentence extended for licence purposes for three years and seven months, Deemster Alastair Montgomerie told her: ’You have acknowledged that you have lit fires in the past and you have admitted liking fires.

’The commission of this arson was within two months of a probation order being imposed which suggests an escalation.’

He urged her to embrace dialectical behaviour therapy (DBT) treatment, telling her: ’If you do, the future for you looks good, if you don’t you could end up being locked up in prison for years and years - the choice is yours.

Given the length of time McGhee has spent on remand, she is unlikely to spend much longer behind bars before she is released.

She was also ordered to pay £500 towards prosecution costs and a total of £2,414 in compensation to her former boyfriend, his father and the flat’s landlord.