UNDERCOVER detectives stopped a heroin deal outside a York supermarket as the dealer was handing over the drug, a court heard.

Louise Marie Ducey, 26, had seven wraps of heroin in her hand and ten more in a Kinder egg in her handbag, said prosecutor Alan Mitcheson.

In an alleyway alongside Morrison's Acomb branch, she did a deal with customer Tracey Elmer.

"Police were so close on the heels of the accused they were able to stop it before it was completed," said the prosecutor at York Crown Court. "Both were arrested at the scene."

Ducey, of Thoresby Road, Acomb, pleaded guilty to possessing heroin with intent to supply it and supplying heroin.

But the Recorder of York, Judge Paul Hoffman, decided not to lock her up after reading that she was extremely motivated to kicking her long-standing heroin addiction, had mental health problems and was not in the best of health following a hip replacement.

"All these matters move me to exercise a degree of mercy that is rarely shown in cases like this.

"You have got to prove to me that you have earned that mercy," he said.

Her crimes merited three years in prison, but instead he gave her a community order with three years' supervision and drug treatment, and 18 days' activities tackling her emotional and employment issues.

"You have got to prove to me that you have earned that mercy and repay it, because if you don't I will lock you up for three years," he said.

"Today you have escaped prison and a long sentence by the skin of your teeth."

He also confiscated £30 drug profits which she had on her at the time of her arrest.

Mr Mitcheson said the police officers were in plain clothes outside the supermarket when they spotted the deal at about 5.25pm on April 26. Ducey had a second Kinder egg on her which was empty.

She pleaded guilty on the basis that she only supplied a small circle of friends and users. Her dealer gave her two free heroin wraps for her own use every time she sold ten. She had been an addict for 11 years.

For Ducey, Taryn Turner said she was very anxious to have drug treatment.