A jilted former City worker found guilty of orchestrating a terrifying campaign of harassment against his ex-girlfriend and her family has been jailed indefinitely with a minimum term of six years.
Al Amin Dhalla, 42, moved in with Dr Alison Hewitt in Brighton, East Sussex, months after meeting her through an elite online dating agency for professionals.
But their relationship soured after Dr Hewitt's family voiced concern over his "unseemly haste" to marry her and over lies they uncovered about his past.
Al Amin Dhalla who was found guilty of orchestrating a campaign of harassment against a doctor and her mother
The couple split after a year, triggering a four-month stalking campaign by Dhalla during which he tried to burn down her mother and stepfather's home and hired a private investigator to snoop on her.
At the height of the harassment, police airlifted Dr Hewitt's mother, Pamela Hewitt, and stepfather, David Gray, from their holiday home on Lundy Island off the Devon coast amid fears for their safety.
In February, ex-City auditor Dhalla was found guilty of offences including arson being reckless as to whether life is endangered.
Today at Lewes Crown Court, he showed no emotion as a judge said he showed a "deliberate and chilling degree of organisation and planning".
One senior detective believed they prevented Dhalla - described by Dr Hewitt's family as a "narcissistic psychopath" - committing three murders.
The trial heard that the Canadian national came to Britain in 2009. A year later he met Dr Hewitt through a London-based internet dating agency.
Jurors were told that he moved himself into her home in Church Place, Brighton, but cracks soon appeared in Dhalla's claims about his background.
Due to Mr Gray working in the defence systems industry, he required security clearance and had to tell his employers about any changes in his family's circumstances.
Through his own inquiries and those of his employer, it emerged that Dhalla had lied about his past.
He falsely claimed that he was 35, an orphan and had lived in Britain for several years. He also did not mention a conviction in Canada for assaulting his uncle with a weapon.
His lies led to him being suspended from his job in December 2010 and in the same month Dr Hewitt, 37, decided to end their relationship.
The court heard that Dhalla's behaviour turned increasingly erratic. He at first refused to move out of her home, forcing Dr Hewitt's relatives to evict him.
Days later, poison pen letters started being received by Dr Hewitt's NHS employer, where she was a trainee doctor at the time, maliciously claiming she acted criminally.
Neighbours of Mrs Hewitt and Mr Gray in the upmarket village of Aston Abbotts, near Aylesbury, Buckinghamshire, were also sent anonymous vindictive letters.
Over the course of the next few months, Dhalla's behaviour became increasingly threatening towards both Dr Hewitt and her family.
In one incident, he stood in the middle of the road and blocked her path as he pleaded with her to give their relationship another chance.
On April 1 last year, Mr Gray and Mrs Hewitt went on holiday to Lundy Island, with only a few friends and family knowing where they were heading.
The next day, after buying a .22 air rifle, a 1.77 air pistol and two mini crossbows, Dhalla was arrested in a field near Chippenham, Wiltshire, while doing target-practice.
Inside his specially-adapted van were masking tape, tools and details of locations, said by the prosecution to include Mrs Hewitt and Mr Gray's holiday spot, their home addresses and hospitals where Dr Hewitt worked.
He was charged with offences related to discharging the weapons and freed on bail, a decision described by detectives as "regrettable".
Days later, while Mrs Hewitt and Mr Gray were still on Lundy Island, he torched their thatched cottage 220 miles away in Buckinghamshire.
After dousing newspapers with petrol, he set fires by the front and back doors, but no-one was hurt, although people were asleep in neighbouring homes.
Such was the concern by police for Mrs Hewitt and Mr Gray at this stage that they airlifted the couple off Lundy to safety.
The case took a further dramatic twist when, a few days later on April 7, Dhalla was spotted at the Princess Royal Hospital in Haywards Heath, West Sussex, by Dr Hewitt's new colleagues.
Posing as a doctor, he tried to get hold of the trainee doctors' rota, including the times when Dr Hewitt would be on duty.
On the same evening, he hired one of a series of cars to drive back to Buckinghamshire.
But in a fit of frustration at seeing his ex-girlfriend's family home surrounded by police, he drove to a nearby police station at Wing instead and tried to burn it down.
Dhalla then visited Dr Hewitt's hospital workplace at 6.30am the following day, about two hours before she was due to clock on.
Staff who had been warned that Dhalla was a potential threat spotted him dressed smartly and armed police arrested him.
In another hire car parked nearby, police found a loaded crossbow, a large knife, fuel cans and a fake doctor's outfit, including a stethoscope.
Police officers also discovered razor blades, a fuel-soaked envelope addressed to Mrs Hewitt and a folder containing the trainee doctors' rota.
He was charged and remanded in custody until his trial but while on remand he sent Dr Hewitt letters, prompting prosecutors to charge him with perverting the course of justice.
Bringing Dhalla to justice involved five forces - Sussex, Devon and Cornwall, Wiltshire, Thames Valley and the Metropolitan Police.
Dhalla was found guilty of arson being reckless as to whether life is endangered, attempted arson, harassment of Dr Hewitt and her mother, theft, damaging property, having an offensive weapon and perverting the course of justice.
He was found not guilty on two counts including putting a person in fear of violence by harassment. He was also cleared of another theft charge relating to papers and cards.
Jailing Dhalla, Judge Charles Kemp said he would not be considered eligible for parole until serving at least six years behind bars.
The judge told him: "You showed a deliberate and chilling degree of organisation and planning. You have tried to put the blame on drink and drugs that you were consuming at the time.
"That is no excuse, but having seen you give evidence I'm satisfied that your methodical planning was deliberate."
The court heard that Dhalla - who wore a crucifix in the dock - had expressed remorse for his actions.
The judge said: "What a pity that you didn't express those sentiments at the outset of these proceedings."
David Lamming, defending, said in mitigation that Dhalla accepts his wrong-doing and wants to return to Canada after he has served his sentence.
He said: "Now that he has had time, after some 15 months in custody and some four and a half months since the trial concluded in February, his position was put to me in summary this morning.
"He said 'I realise what I did was wrong. I'm very ashamed. I was under a lot of stress because of the relationship with Alison and the actions of the Hewitt family'.
"But he instructs me to tell the court that he accepts full responsibility for what he has been convicted, which was out of character.
"What he says is 'Now I just want to serve my time, whatever the sentence is, to go back to Canada and get on with my life'."
Outside court afterwards, the family of Dr Hewitt condemned Britain's border controls after it emerged the authorities were alerted to the threat Dhalla posed to them.
Her stepfather told reporters: "This case has served, yet again, to illustrate the deficiencies in our current border controls.
"Mr Dhalla should never have been let in to this country.
"On discovering his violent criminal record in his native Canada, we informed the Home Office and the Border Agency of the threat he posed to us.
"They ignored our pleas for help, and he went on to commit very serious crimes for which today he has been sentenced.
"Even now the UK has no effective way of ensuring Mr Dhalla does not return after deportation and we are therefore in fear of our future safety.
"It is time this Government took the security of its innocent citizens seriously."
Dhalla faces deportation back to Canada if he is ever released.
Detective Superintendent Nev Kemp, from Sussex Police, the leading force in the investigation, said: "This sentence sends out a strong message to anyone thinking of harassing another person in this way.
"We take domestic abuse very seriously and no stone will be left unturned in tracking them down and bringing them to justice.
"Dhalla is a dangerous, narcissistic individual who knew no boundaries during his focused harassment campaign against Alison and her family.
"No-one should ever have to fear for their lives in this way following the break-up of a relationship.
"His victims had every aspect of their daily lives invaded and were made to feel incredibly vulnerable and isolated.
"I would like to acknowledge their bravery and thank them for working so closely with the police investigation and, in doing so, helping put Dhalla behind bars for a considerable amount of time."
Detective Chief Inspector Rebecca Mears, of Thames Valley Police, said: "This was a serious case of stalking and a successful investigation thanks to the joined-up working of the five police forces involved.
"I believe this case has demonstrated how serious stalking cases can be and how the actions of a stalker can have a huge impact on the lives of the victim and their families.
"I welcome the sentence given by the court today and would like to praise the courage of Alison and her family, who, despite going through a terrible ordeal, have found the strength to fully support the police investigation."