Prof Warnke specialised in tumours

Professor Peter Warnke, 48, is being investigated by the University of Liverpool and is excluded from duties at the Walton Centre for Neurosurgery.

A Walton Centre spokeswoman confirmed an investigation was under way and a member of staff had been suspended.

"This is not a clinical competence issue," she said.

'Ethical consent'

The suspension follows claims that samples were delivered to a private firm in Germany without gaining the ethical consent of patients.

Prof Warnke was suspended within days of a whistleblower launching a legal action against the university and trust.

The number of patients involved has not been disclosed.

The centre spokeswoman said: "We can confirm that research matters have been investigated and are being dealt with through the university's formal disciplinary process."

Samples allegations

Prof Warnke, whose specialist interests include tumours, said: "This is being dealt with by the university.

"I don't want to talk about it. Talk to the university about it."

The inquiry is examining allegations that the authorities were misinformed over the samples.

A whistleblower has taken his case to an employment tribunal and to the High Court.

But the tribunal case has been put on hold until an action for alleged breach of contract and harassment has been completed at the High Court in Liverpool and is expected to be heard later this year.

The university was unable to say how many samples were taken or whether proper consent was given.