 She was detained in a camp in Lamu until January 1961, and records that she was raped and impregnated by a British prison officer while detained there.After her release from detention, Wambui joined Tom Mboya’s Nairobi People's Convention Party as leader of its Women’s wing.This party later became part of the Kenya African National Union (KANU), and in 1963 Wambui was elected head of the women's wing of KANU and was also involved in Kiama Kia Muingi, an organisation that was a successor to Mau Mau.