A mother of two was given a hospital detention order today for causing the death of an 11-year-old former Birmingham boy by dangerous driving as he walked home from church.

Hannah Saaf, 28, of St Michael's Hill, Bristol, previously pleaded guilty at Bristol Crown Court to killing 11-year-old Sam Riddall, whose famliy used to live in Kings Heath.

Saaf knocked down and killed Sam in Westbury-on-Trym, Bristol, on May 1, while driving a white Ford Focus estate.

Prosecutor Robin Shellard told the court Saaf was driving at twice the speed limit, at least 61mph, before she attempted to stop.

Sam was killed as he walked with a group of friends from a church youth service.

The court heard the mother of twins fled the scene and a nine-day police hunt for her ended when officers tracked her down to a field in Somerset.

Officers arrested Saaf on May 10 in the village of Publow, where she had been sleeping in a barn.

Sentencing Saaf, who appeared dressed in a grey pinstripe suit, Judge Simon Darwall-Smith said no sentence could compensate for the tragic loss such as this.

He said if it were not for Saaf's mental state she would have faced "a very substantial custodial sentence".

He handed Saaf an indefinite hospital order under the Mental Health Act and a restriction order as well.

Speaking outside court Sam's father, Martin Riddall, said: "In four days time we celebrate Christmas and it's going to be our first Christmas without our Sam.

"It's going to be very hard for us indeed, because we still miss him very much. At Christmas we remember that God sent his son Jesus into the world to bring peace.

"It's the same God that is giving us the strength and helping us to forgive Hannah for the terrible thing she's done to us by killing our son.

"It's not easy, it's not going to be easy. But with God's help we know that it is possible."

Saaf sobbed uncontrollably throughout the hearing as Sam's father and his mother Rachel Riddall sat in the front row of the public gallery.

Opening the case, Mr Shellard said Sam was walking away from church in Westbury-on-Trym with the father of one his friends, Dr Peter Hargood, who was also clipped by Saaf's car.

"As he walked he became aware of a car coming towards them," he said. "Dr Harbord was aware the speed limit was 30mph so was shocked to see the car heading towards them at speed."

Mr Shellard went on: "Dr Harbord could hear the boys screaming behind him but was unaware Sam had been hit.

"He found Sam close to the door being administered first aid. Due to his medical training he realised straight away he was dead."

Mr Shellard told the court other witnesses noted the car was driving at great speed, and saw a woman flee from the scene.

A post-mortem examination concluded Sam's injuries were "not survivable" and death would have been instantaneous.

Mr Shellard said an accident investigation conducted by the police revealed Saaf was driving no less than 61mph before she hit the brakes, leaving 59.54 metre long skidmarks across the road.

He said the DVLA revoked Saaf's licence over concerns about her mental health in February.

Between February 2008 and April 2009 she was detained under the mental health act and discharged four times, Mr Shellard said.

Mr Shellard said Saaf had been smoking cannabis and listening to music with friend Caleb Morris and had no sleep the night before the tragedy.

Mr Shellard went on: "After the crash Hannah Saaf disappeared. She was located in countryside south of Bristol.

"At the police station, she sat down and burst into tears and said "I've stolen a life"."

Saaf made no comment during police questioning, but handed over a statement prepared by her solicitor, in which she admitted driving the vehicle.

She said: "Since I've had the accident I've been alone and very scared. I've found myself in a grave and serious situation and felt out of my depth.

"I'm deeply upset with the loss of Sam's life, as a mother myself I feel greatly for his parents. I feel deep remorse and am very sorry for what has happened."

Defending Saaf, Ian Kelcey said his client was "deeply remorseful for what happened on that tragic day".

Saaf previously pleaded guilty to causing death by dangerous driving, driving not in accordance with a licence, failing to stop at an accident, failing to report an accident and driving without insurance.

Judge Darwall-Smith banned Saaf from driving for five years before sectioning her under the mental health act.

He said: "This offence has all the aggravating features in this offence. You were not permitted to drive at all, you were clearly under the influence of cannabis, and you were doing so while driving twice the speed limit allowed.

"Finally, you left the scene having killed the victim.

"There's no sentence a court can pass that will ever compensate for a tragic loss such as this. I have read the victim impact statements and they make heartrending reading."