BBC Scotland Correspondent Colin Blane: "Boy was praised for handing in drugs"

He is reported to have given the drug to a teacher, saying: "Take this, please, because it's killing my mum."

The news comes just days after an 11-year-old was found with heroin in his satchel at a Glasgow primary school.

Police said that on 2 October, a boy was found in possession of £25 worth of heroin at Borestone primary school, Stirling, central Scotland. The boy was praised for his actions and there was no suggestion he had done anything wrong.

Police were called to Borestone Primary

Stirling Council, which runs the school, said it was an isolated incident.

"We believe it was a cry for help from the boy, whose action in handing the drugs to the teacher was very brave," said council spokesman Don Monteith.

"The school handled the whole issue remarkably well ... It happened almost four weeks ago, and we don't think it is indicative of a drugs problem at the school," he said.

Borestone Primary School serves parts of the St Ninians area which is known to have a serious heroin problem.

The BBC's Sean Bricknell: Council spokesman says it was a cry for help

Stirling police interviewed the boy and his family and a 26-year-old local woman was reported to the procurator fiscal at Stirling.

The head teacher, Joy McFarlane, wrote to parents reassuring them that action would be taken. A drugs awareness team then began working in the school to strengthen the anti-drugs message to pupils.

Parents at the school seemed satisfied with the way the matter was handled.

"The first we knew about it was when we received the letter. We were shocked, but it appears to have been a one-off and at least we were told," said one mother.

Earlier this week Scottish Education Minister Helen Liddell promised to set up a School Drug Safety Team after an 11-year-old pupil was found with £500 worth of heroin at Craigton primary school in Glasgow.

Helen Liddell: "Teachers acted sensitively"

Reacting to the latest news she said: "This is a shocking and heartbreaking incident coming as it does around the time when we learned of another incident in Glasgow.

"But I have the greatest admiration for the teachers in both cases who dealt with this so sensitively and efficiently."

In a second case, a young boy was discovered with a large quantity of what is believed to be cannabis at a school for children aged four to eight in Farnham, Surrey.

Police found more drugs at his home last week. A 27-year-old woman and 26-year-old man were arrested and released on bail.

A spokesman for Surrey police said: "We do not suspect the child was involved in the misuse of drugs."

Drugs Czar Keith Hellawell: "We must stop parents putting their children at risk"

The UK Anti-Drugs Co-ordinator Keith Hellawell said drug-taking parents must realise they are putting their children at risk.

"They need to stop it and we need to deal with it," he told BBC TV's One O'Clock News.

He insisted that at the moment it is rare for young children to be used to seeing drug use.

"What we are doing in schools is helping children understand the nature substances generally, legal as well as illegal in order that they can understand the consequences of getting involved."