"Video game giant Electronics Arts said Thursday it's buying mobile games maker Jamdat Mobile, the name behind popular games like Tetris, for $680 million in a move to expand its reach in the mobile gaming market.

The gaming software company will pay $27 per share in cash for Jamdat's Common stock, representing a 20 percent premium over Jamdat's closing price of $22.45 on Wednesday.

The news came after the market closed. Jamdat's stock jumped $4.28 or about 19 percent to $27.05 in after-hours trading, while EA stock fell $1.41 to $54.34. EA will also assume Jamdat's outstanding stock options.

"Together we intend to build a leading global position in the rapidly growing business of providing games on mobile phones," said EA CEO Larry Probst about the acquisition.

Redwood City, California-based EA and Los Angeles-based Jamdat together plan to publish more than 50 games for mobile phones in the first 12 months following the completion of the acquisition. The deal is expected to close in EA's fiscal fourth quarter, which ends on March 31, 2006, and is subject to regulatory approval."