A gap-year student from Australia who helped teach sport at an independent school in Aberdeen has been sent home after claims of inappropriate use of a social networking site.
Robert Gordon's College and Grampian Police have launched an investigation into the man.
A spokeswoman for the college refused to divulge the nature of the alleged comments on the internet.
She denied media reports the man had asked a student to sleep with him.
Det Con Evelyn Simpson, from Grampian Police, said: "We can confirm that we are investigating, along with out partners in the joint child protection unit, a child welfare issue involving inappropriate conduct by a member of staff aged in his 20s at a school in Aberdeen.
"These inquiries are continuing and it would be inappropriate to comment further."