A former Japanese defence minister has been elected as the first woman governor of the Japanese capital. Koike was pronounced the winner by public broadcaster NHK after polls shut at 8pm (12pm BST). Before cheering crowds, Yuriko Koike said: "I will lead Tokyo politics in an unprecedented manner, a Tokyo you have never seen."
The 64-year-old is also a former TV anchorwoman, who speaks fluent English and Arabic – which she learned as a student in Cairo. Koike was the interviewer for the Nippon TV special, Colonel Qaddafi and Yasser Arafat. She served as environment minister, in office from 2004-2006.
She has compared herself to Hillary Clinton and was once tipped as having the best chance to be Japan's first female prime minister. But she was beaten when running for office in 2008.
One of her tasks will be to put a stop to the financial irregularities foreshadowing Tokyo's preparations to host the 2020 Olympic Games. The previous two governors were forced to resign.
Yoichi Masuzoe, the previous governor of Tokyo stepped down from office on 15 June, after it came to light that he had spent more than ¥200m yen (£1.32m) on eight overseas trips during his two years in office, according to a Guardian report.
The costs of the Tokyo Games has been doubled, and some estimate it will cost triple the original amount allocated of ¥730bn (£5.4bn), said the Japan Times. Further embarrassments include organisers withdrawing the games' logo after its designer was accused of plagiarism.
Koike's manifesto included improving facilities for the underprivileged in Japan's society. "As the (central) government pushes for a society where 'women can shine', I think a female governor of Tokyo would be the perfect embodiment of that idea," she said at a news conference.
The 64-year-old promised aid for children living under the poverty line and public nursing services for the elderly.