South Korea's Lee Sedol, the world's top Go player, right, puts the first stone against Google's artificial intelligence program AlphaGo, as Google DeepMind's lead programmer Aja Huang, left, sits during the Google DeepMind Challenge Match in Seoul, South Korea, March 9, 2016. [Photo/Xinhua]

SEOUL - Google's computer program AlphaGo on Wednesday unexpectedly defeated world human Go champion Lee Sedol of South Korea in the first of their five-game match, taking a 1-0 lead with an automatic victory by a wide margin.

Lee, the world champion of the ancient Chinese board game Go in the past 10 years, was shockingly defeated by AlphaGo, a computer program developed by Google's London-based artificial intelligence (AI) arm.

It marked the first time that AI beats the world human champion at Go, which has been regarded as the last game humans can dominate in matches with computer programs.

The five-game match will run through next Tuesday, with the second game set to be held on Thursday.