SEATTLE -- The head of Amazon.com Inc.'s online search effort is leaving to join Google Inc., the latest in a series of high-profile hires for the search engine leader.

Udi Manber, who has been chief executive of Amazon.com's A9 subsidiary, will be a vice president of engineering at Google, spokeswoman Lynn Fox said Tuesday. She declined to provide more details, including when Manber will start and what specifically he will work on.

Mr. Manber's defection marks the latest coup for Google, the Mountain View, California-based search engine company that is proving a formidable foe for many technology industry titans.

In September, the company snagged Internet pioneer Vinton Cerf from MCI Inc. Also last fall, Microsoft Corp. and Google waged a court battle over Microsoft executive Kai-Fu Lee's decision to resign from Microsoft to oversee Google's efforts to open a research center in China. That case has since been settled.

Google's other recent notable hires including longtime Microsoft executive Mark Lucovsky and former eBay Inc. executive Louis Monier, who was also a key player in the development of the first search engine, AltaVista.

Mr. Manber is being replaced at A9 by David Tennenhouse, effective immediately. Craig Berman, spokesman for Seattle-based Amazon.com, said Manber would be at A9 until Friday. Tennenhouse was previously a vice president and director of research at Intel Corp.

Google is by far the leader in the search engine field, commanding 46.3 percent of the U.S. market according to the latest November data from Nielsen/NetRatings. By comparison, Amazon.com's A9 ranked 29th, with 0.1 percent of the market.