The inspector has been suspended following the incident, which is alleged to have occurred on 26 January during the inspection of Crown Woods Secondary School in Eltham, south-east London.

The Office for Standards in Education (Ofsted) took action after a complaint from the school's headteacher, Linda Neal.

The company contracted to carry out the inspection, National Inspections, removed the inspector from its team.

Once a school inspection has begun, it is highly unusual for an inspection team to be changed for reasons other than illness.

Ofsted issued a statement which said: "The contractor has dealt with this correctly, in line with its own complaints procedures and Ofsted's Quality Assurance requirements.

"Ofsted is also investigating the matter and has suspended the accreditation of the team inspector.

"Ofsted regards the alleged behaviour of the inspector as unacceptable."

The report of the Macpherson inquiry into Stephen Lawrence's murder is expected to be presented to the Home Secretary, Jack Straw, on Wednesday.

The teenager was knifed to death at a bus stop in Eltham in April 1993 in what an inquest described as a racist attack.

Three suspects were acquitted after Stephen's parents brought a private prosecution. The Crown Prosecution Service dropped murder charges against another two.

But all five suspects - Neil and Jamie Acourt, Luke Knight, Gary Dobson and David Norris - were forced to appear before the public inquiry into the police's investigation of the murder.