BEIJING, Apr. 27 (AP) -- Baidu.com Inc., China's most popular Internet search engine, said Friday its first-quarter profits jumped by 143 percent on strong traffic growth and higher advertising revenues.

"We believe that the best is ahead of us," CEO Robin Li said in a conference call with analysts.

Profits rose to 85.5 million yuan (US$11.1 million; €8.1 million), up from 30.6 million yuan (US$4 million; €2.9 million) in the same quarter of 2006, the company said. It said total revenues rose by more than 103 percent to 275.6 million yuan (US$35.7 million; €26.2 million).

Earnings were 2.47 yuan (32 U.S. cents; 24 euro cents) per American depositary share, up from 0.89 yuan (0.11 U.S. cents; 0.08 euro cents) per share in the same period of 2006.

Baidu's U.S. shares gained more than 22 percent in after-hours trading.

Li said traffic increased "quite quickly" after the Chinese New Year holiday in February, but released no details.

The number of active online marketing customers during the quarter grew to more than 112,000, up nearly 4 percent from the previous quarter, the Beijing-based company said.

It forecast more strong revenue growth in the coming quarter.

Baidu has about 55 percent of China's search engine market, ahead of Google Inc. with 21.7 percent and Yahoo Inc.'s China arm, which has 7.2 percent, according to market data firm iResearch Inc.

Baidu has been expanding its offerings beyond search. During the first quarter, it launched a Web log service and ventures with Viacom Inc.'s MTV division to distribute music videos online and with recording company EMI Group Ltd. in streaming music.

Baidu's U.S.-traded shares added $24.63 to $134 in after-hours electronic trading, having earlier closed up $4.69, or 4.5 percent, to $109.37 on the Nasdaq Stock Market.