Britain's biggest exam board has been accused of censorship after it removed a poem containing references to knife crime from the GCSE syllabus.

Officials at the AQA board said their request that schools destroy the anthology containing the Carol Ann Duffy poem Education for Leisure had been triggered by concerns in two schools about references to knives. A spokeswoman confirmed the decision had been made in the context of the current spate of knife-related murders.

But poets yesterday condemned the move, saying such "censorship" fundamentally missed the point of the poem, which they said could help children debate the causes of street violence.

The poem starts:

Today I am going to kill something.
Anything.
I have had enough of being ignored and today
I am going to play God.

It describes a youth's yearning for attention and a journey to sign on for the dole, and makes references to the killing of a goldfish. It ends ominously with the youth walking the streets armed with a bread knife.

Duffy's literary agent, Peter Strauss, said: It's a pro-education, anti-violence poem written in the mid-1980s when Thatcher was in power and there were rising social problems and crime. It was written as a plea for education. How, 20 years later, it had been turned on itself and presented to mean the opposite I don't know. You can't say that it celebrates knife crime. What it does is the opposite.

A spokeswoman for AQA confirmed there had been three complaints, two referring to knife crime and a third about the description of a goldfish being flushed down the toilet.

The AQA spokeswoman said: The decision to withdraw the poem was not taken lightly and only after due consideration of the issues involved. We believe the decision underlines the often difficult balance that exists between encouraging and facilitating young people to think critically about difficult but important topics and the need to do this in a way which is sensitive to social issues and public concern.

Teachers have attacked politicians' meddling in the national curriculum and the censorship of English literature, warning against the schools secretary, Ed Balls, winning the power to dictate what pupils read and learn.

Delegates at the annual conference of the Association of Teachers and Lecturers (ATL) voted to raise the issue of censorship with Balls following the banning of Carol Ann Duffy's poem Education for Leisure, which refers to knife crime, from an AQA exam board anthology last year after extreme pressure from a group of MPs.

Teresa Dawes, an ATL member from Park House school in Berkshire, said: It rather makes one think of historical book burnings and all that implies. If young people don't get the opportunity to think critically about difficult but important topics in school, topics that often trouble them, where do they discuss them? The idea of any politician determining which parts of history or science children are taught or which books they study is indeed a chilling and frightening one