A Chesterfield headteacher will not be at her school 'for the foreseeable future'.
Teachers at Hasland Hall Community School - whose headteacher is Ruth Moore - have held a number of strikes this year amid concerns about staff treatment and a lack of pupil discipline.
Now, in a letter to parents, Hasland Hall's chair of governors Pat Bell said: "I write to inform you that Miss Moore will not be in school for the foreseeable future.
"Mr Edmonds will be acting headteacher during this time.
"Our number one priority is ensuring that all young people get the very best education and to do this we must all continue to work together."
The Derbyshire Times has asked the school for more information and is awaiting a response.
Before one of the Hasland Hall strikes in the summer, a spokesperson for the National Association of Schoolmasters Union of Women Teachers said the walk-out was in response to staff workload, student's indiscipline and concerns about attitudes to staff safety.
Miss Moore previously told the Derbyshire Times: "We are very disappointed about the NASUWT decision to take strike action.
"School leaders have worked hard to engage with and work closely with students, staff and all trade unions to address any concerns when they have arisen and to effectively manage and make improvements in these areas."