A doctor who posed as a 13-year-old girl on the internet to chat with other teenagers in a sexually explicit way has been struck off.
Dr Thomas Dent, 40, of Newbury, Berks, claimed to be "Katie Beckinsale" to talk to youngsters about sex, a General Medical Council (GMC) panel heard.
The then National Institute of Clinical Excellence (Nice) director was caught while using his laptop on a train.
The GMC found him guilty of serious professional misconduct.
He did not contest the charge or attend the two-day GMC fitness-to-practise hearing in Manchester.
He will not be allowed to practise medicine until further notice.
After Dr Dent was caught on the train by a special police constable in May 2004, he gave false details of his name and address and disposed of his home computer.
But he was spotted on the train 10 days later and arrested for grooming children.
Despite giving false information, the Crown Prosecution Service (CPS) decided not to prosecute him due to a lack of evidence.
Instead, he was given a five-year risk of sexual harm order warning him not to engage in sexual conversations with children online.
At the end of the hearing, the GMC concluded the case was "extremely serious" and involved "the misleading and exploitation of vulnerable young people for sexual gratification".
Dent has since resigned as director of the Institute's Interventional Procedures Programme.