A maths tutor at one of the country's top public schools has been forced to leave after being accused of "inappropriate behaviour" with the head girl.
Andrew Crozier resigned from Wellington School in Somerset after an alleged affair with 18-year-old Keziah Trump.
The boarding school has sent a report on the incident to the Department for Education and Skills (DfES).
It will decide whether Mr Crozier, aged in his 20s, is guilty of misconduct.
Headmaster Alan Rogers said in a statement: "A teaching colleague did resign on Friday 21 February, because of inappropriate behaviour with a sixth-form student.
"The teacher has now left Wellington School and the area and a report has been submitted to the DfES."
Keziah's father David confirmed to the Western Daily Press that his daughter had been involved with a teacher who had since resigned.
"They are both adults," he said.
Somerset County Council said social services had been alerted and had been in touch with police.
An Avon and Somerset Police spokesman added: "Officers from the force's child protection unit have liaised with the council's social services department but there is currently no investigation into this matter."