In what teachers have described as the "tip of the iceberg", police figures have revealed that several Class-A drugs, including heroin and crack cocaine, were seized from school children across the UK between 2011 and 2014.

In 2,000 similar incidents, police from across England and Wales found the drugs amongst other illegal substances with school children, revealed the Press Association news agency (PA).

Cannabis was found in 625 cases out of the total and cocaine in 27 with LSD, amphetamines and ecstasy, among other drugs found.

PA obtained the figures under the Freedom of Information Act after sending requests to nearly 34 police forces from across the UK asking them to reveal the number of times illegal drugs were seized from March 2011 to the end of 2014, reported BBC News.

Two cases of heroin possession were reported in the West Midlands, Surrey and Greater Manchester and Hertfordshire.

Four incidents reportedly involved children between the ages of eight and 10 who were found with cannabis.

The highest number of drug seizures were reported in Hampshire where a total of 229 incidents were recorded.

"[Drugs being found on school premises is] worrying as it will often only be the tip of the iceberg of what young people are encountering on the streets.

"Teachers and school leaders are always alert to the potential for young people being involved in drug or alcohol abuse," said Chris Keates, general secretary of the National Association of Schoolmasters Union of Women Teachers (NASUWT ), reported BBC News.

Meanwhile, a London-based human rights activist, Qasim al-Hashimi, told Iran's Press TV: "This is a very sensitive and dangerous subject. I would say that school, authorities mainly and parents secondly are to blame.

"School and authorities should make sure that their properties like school, education, and colleges especially for youngsters are protected.

"[Schools] should [also] make sure that there is a checkpoint especially for those schools that they are well-known and famous for drug distribution. We have not yet seen a checkpoint or an intention to fight such behaviour at those schools."