A MENTAL health patient pleaded to be sectioned just hours before stabbing two strangers in a murderous Bexleyheath knife attack, a court heard.

Nicola Edgington is accused of murdering 58-year-old Sally Hodkin, moments after attempting to murder then 22-year-old Kerry Clark on the morning of October 10, 2011.

Edgington, 32, begged mental health staff at the Bracton Centre in Dartford for help during an early morning telephone call from Queen Elizabeth Hospital, Woolwich, a jury at the Old Bailey heard today. (January 8)

The unemployed long-term mental patient made the agitated 4.45am call during a night of strange behaviour prior to the alleged attacks, according to prosecutor Mark Heywood QC.

He said she told a nurse on the phone "I am a very dangerous schizophrenic.

"If you don’t help me I’m going to hurt someone."

At 7.05am Edgington left the Oxleas Unit at QEH without warning and took two buses to Bexleyheath, a jury of seven men and five women was told.

Getting off at Arnsberg Way at around 8.15am, she went straight to Asda and bought a 12-inch kitchen knife before tearing away the packaging inside the store.

Mr Heywood said: "You would think that is the sort of weapon, faced with a selection on a shelf, that someone might choose to kill."

Miss Clark was then attacked outside Asda on Broadway while waiting for a bus to work in Dartford Heath.

Mr Heywood said: "What she saw would have horrified anyone, but she had no time to think.

"It was this defendant coming for her, now with that large Asda knife held aloft in one hand, aiming the blade centrally at the upper part of her chest.

"The woman coming for her was shouting 'you f***ing bitch, you f***ing bitch'."

Reacting swiftly, Miss Clark was able to fight off the ferocious attack and disarm Edgington before telling her assailant to "jog on" after she demanded her "f***ing knife back", the court was told.

Edgington then proceeded calmly across the road to the south side of Broadway "as if nothing had happened", according to witnesses.

They said she stole an 11-inch steak cutting knife from the British Meat Market while butcher David Russell’s back was turned, and ran towards Albion Road.

Within five minutes and 250m of the first assault the defendant is accused of meeting Sally Hodkin by the War Memorial and nearly decapitating the victim in a "swift, forceful and truly ferocious attack".

Mr Heywood said: "No doubt Mrs Hodkin tried to defend herself.

"In truth she had no prospect of doing so.

"The defendant, no doubt wise from her recent experience, gave her no chance."

After at least four separate stabbing motions Mrs Hodkin was left with a series of "gaping" wounds including a 20cm incision "encircling nearly 180 degrees" of her neck, the jury was told. She died almost immediately.

The court heard Edgington was convicted of the manslaughter of her mother, committed in November 2005 after the prosecution accepted a plea of diminished responsibility.

Mr Heywood told the jury: "On this occasion it will be for you to decide."

Edgington, of Ambedkar House, Flavell Mews, Greenwich, pleaded not guilty to one charge of murder and one of attempted murder.

The trial continues.