A council education chief quit today after admitting she worked with the IRA in the 1970s.
Conservative councillor Maria Gatland resigned as a cabinet member on Croydon Council after being exposed as the author of a "kiss and tell" book about the provisionals.
The book described how, among other tasks, she acted as an interpreter for the movement on an arms-buying trip to Europe.
The council appears to have been unaware of her past because the book was published in 1973 under her maiden name, Maria McGuire.
A spokeswoman for Croydon Council said today: "The council has been advised that Maria Gatland has resigned as cabinet member for children, young people and learners.
"This follows emerging news of her connection to the Provisional IRA - which has come as a complete shock to Croydon.
"Officers understand she has been urged to resign from the council. It is also understood that urgent steps are being taken to replace her as cabinet member."
Ms Gatland's book - To Take Arms: My Year With The IRA Provisional - was described in a review in Time magazine in 1973 as a "kiss and tell story" about her relationships with the movement.
It was written after she became disillusioned with the provisionals, and fled to England. The turning point was apparently when 20 bombs were detonated in Belfast on 21 July, 1972, killing 11 people and injuring more than a hundred.
"Almost for the first time, I wondered about the crippled and the widowed and the lives that had been changed forever," she wrote.
She is believed to have been sentenced to death by the IRA as a result.
Ms Gatland's activities when in her 20s only emerged after cryptic clues in a public meeting yesterday.
The Croydon Advertiser reported that Peter Latham, a leader of the local Save Our Schools campaign, referred to her as "Councillor McGuire".
Apologising and suggesting he was a bit mixed-up, Dr Latham added that he was a devotee of Irish history and had been reading a book about the IRA which "you, Councillor Gatland, might have heard about as you are Irish".
According to the newspaper, Ms Gatland has been suspended by the local authority's ruling Conservative group pending an investigation.
"I have resigned. I am not prepared to say anything more at this stage," she told the Advertiser.