A person posing as a Therapeutic Goods Administration official has walked into a Melbourne health clinic and demanded vaccination posters be removed.

The Commonwealth organisation said it was aware of the impersonation and warned anyone else thinking of trying the trick that they would be breaking the law.

“Impersonating Commonwealth public officials is a criminal offence,” the TGA said on Thursday.

“We advise individuals who may be encouraged to impersonate an officer of the TGA that this is a serious criminal offence that may lead to prosecution.”

The TGA said it broadly prohibits the advertising of prescription medicines including vaccines. However, that is not the case when the medication is authorised or required by a government authority.

“Posters relating to vaccines and vaccination sanctioned by the Australian government Department of Health under the National Immunisation Program are permitted,” the TGA said.

“As part of an important public health campaign, this material is appropriate and legal, and provides important health information to consumers.

“If clinics and health professionals produce their own public information materials, we advise focusing on services, rather than specific products to avoid a breach of the advertising requirements.”