Image copyright Other Image caption The children's father, Gary Clarence, was in South Africa at the time of the deaths

A mother charged with killing three of her children has been remanded under the mental health act to a secure hospital.

Tania Clarence, 42, appeared at the Old Bailey via a video-link accused of killing her three-year-old twin sons and four-year-old daughter.

The disabled children were found at their home in New Malden, south-west London, on 22 April.

The bail hearing also heard the cause of death was probably suffocation.

Tests due

Mrs Clarence is accused of three counts of murdering a child aged over one year old between 20 April and 23 April.

Spinal Muscular Atrophy A genetic disorder that affects nerves responsible for muscle function.

It causes the muscles to waste away over time, which can lead to skeletal deformities, such as abnormal curvature of the spine, and problems walking, eating, drinking and breathing.

It is rare, affecting one in every 6,000 babies born in the UK.

However, the most common of the three forms of SMA - type 1 - is the most severe, and usually proves fatal in a child's first year.

Type 2 SMA is a milder form of the disorder which usually becomes apparent between six and 18 months of age.

Children with type 2 can live to their teenage years or adulthood.

The most mild form of SMA does not usually affect life expectancy.

Her sons Ben and Max and daughter Olivia all suffered from type 2 spinal muscular atrophy.

Judge Brian Barker, the Recorder of London, allowed Mrs Clarence to be released from prison, and remanded her to a secure hospital because it was an "exceptional case" and to allow her to receive hospital treatment.

"It isn't bail, but what we are doing is ordering for her to be subject to a Section 35 Order under the Mental Health Act, so she can then be remanded effectively for review of her condition," he said.

The court heard police are awaiting the results of toxicology tests on the children before a definite cause of death can be established.

The court heard the children's father Gary Clarence was away in the family's native South Africa with their eldest daughter, Taya, at the time of the deaths.

A hearing where Mrs Clarence could enter a plea will take place at the Old Bailey on 15 May.