A primary school teacher who allegedly called pupils "inbred" and "thick" on Facebook may face disciplinary action.
The insults were bandied about on the social networking site during a conversation involving four teachers - apparently even including the head Debbie Johnson.
An investigation has been launched after parents expressed their outrage at the derogatory comments, which have been attributed to Nyanza Roberts, a teacher at Westcott Primary School, Hull.
According to parents at the primary, copies of the conversation were posted onto fences surrounding the school in a protest over what was said.
The Facebook chat was allegedly started by teacher Stuart Clark, who wanted to air his "fed up" feelings over "bumping into children in town".
Roberts is said to have responded, adding "No wonder everyone is thick ... inbreeding must damage brain development."
Johnson then replies: "You're really on one today mrs", to which Roberts says, "Haha, I'm actually in a good mood!! If anyone reading this is offended, then get a grip!!"
Parent Emma Bywood, 30, has two children at the school vented her rage at the comments to the Daily Mail.
"My son came home on Monday and I had to explain to him what inbred meant.
"I'm fuming", she added. "If he wasn't in year six, I would be taking him out of the school. But he is starting his Sats exams after Christmas."
Both the school's governors and the local education authority, Hull City Council, have launched inquiries.
Vanessa Harvey-Samuel, head of learning at council, said they would be "investigating the matter thoroughly" and appropriate action would be taken.
"We are taking this very seriously and are pleased to support the governing body. All professionals need to be mindful of professional expectations in relation to all communication, even in their own time.
"All schools have been issued with guidance for professionals that work with children and young people about the appropriate and responsible use of social networking sites, such as Facebook", she added.
The school has now issued an apology over the incident and the comments have been taken down from Facebook.
In a letter to parents, chair of governors Mary Wallace said:
"As you may be aware, there has been publicity around remarks allegedly made by members of Westcott school staff on Facebook. I write on behalf of all the staff and members of the [governing body]to express a sincere apology for any offence caused by these remarks. I would like to reassure you that the matter is being taken very seriously. I have asked the local authority to undertake the investigation on behalf of the board in the interest of impartiality. Our priority, as always, is the care and protection of our children and the continuity of their learning. I can assure you that every effort is being made to ensure this will remain the case."
Wallace added the school would be investigating the matter and "appropriate action" would be taken.
But parent Emma Bywood was not satisfied with the letter, saying the chair of governors should not have been left to say sorry.
"It should be thoroughly investigated. Nobody has admitted anything in the letter and it's an apology from someone who hasn't done anything."