Education Secretary David Blunkett said that Selhurst High School in Croydon was one of two schools still giving cause for "serious concern". Progress was "limited" while "competency procedures against 15 teachers are ongoing".
In fact, only five teachers' competence is in question. The Government's statement wrongly implied that the process would be completed by Christmas - which was reported by the BBC as meaning that 15 Selhurst teachers would be sacked by the end of this term.
David Sands, Croydon education director, has written to every secondary headteacher in the borough saying that the Department for Education and Employment was mistaken and expressing anger at the damage to morale this has caused.
The letter also says that Croydon had "many conversations" with the DFEE before the Government's announcement to ensure ministers understood that just five Selhurst teachers were involved, but "unhelpful and incorrect statements were nevertheless made".
"Morale at Selhurst has been hit once more and we are deeply sorry that this has occurred. We expect to meet the minister, Stephen Byers, soon and we will be making our views known clearly." The letter is also signed by education committee chair Hugh Malyan.
Mr Sands confirmed to The TES that Croydon had made clear to the DFEE before the announcement on November 10 exactly how many teachers at Selhurst were involved in competency proceedings and at what stage these proceedings were.
In the case of the five teachers, Mr Sands implied that Croydon would rather help them improve than sack them. "The quickest way to improve the quality of education is to help teachers to improve rather than get rid of them".
Meanwhile, National Union of Teachers general secretary Doug McAvoy has accused Mr Blunkett of circulating a "dangerous lie". In a letter to the Education Secretary, Mr McAvoy urges him to correct the statement immediately. "The facts relating to Selhurst high are inaccurate." He also points out that Selhurst's percentage of pupils gaining five A-Cs at GCSE has jumped from 19 per cent in 1995 to 27 per cent this year, putting it third out of the borough's seven local authority-controlled secondaries.
Dave Harvey, a Croydon NUT spokesman, said that last week's announcement had further damaged morale at Selhurst, despite the fact that the school had moved to a newly-refurbished building this term. "At the end of last term, there was one teacher taking early retirement. By the beginning of this term, there were five more."
Last July, Croydon appeared willing to pioneer the Government's proposed "fast-track sacking" policy, but backed down under threats of NUT strike action. The five teachers at Selhurst are being investigated under traditional local authority procedures.