Story highlights Gambian marble voting method praised for being "more transparent, credible, and fair"

But Internet and phone lines were blocked on eve of election

(CNN) He has ruled Gambia with an iron grip for the past 22 years, but President Yahya Jammeh has suffered a shock election defeat and will concede power to his opponent Adama Barrow, the country's electoral commission told CNN.

Joseph Colley, director of communications for the commission, said: "The President will make a television statement conceding the election within the next three hours."

"Our commissioner was called and informed and we are confident the president will concede," he added.

Earlier, the head of the commission Alieu Momar Njie, told reporters in Gambia, "It's really unique that someone who has been ruling this country for so long has accepted defeat."

Barrow, a property developer, won more than 45% of the vote with 263,515 ballots cast for him.

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