on Thursday beat Wall Street expectations for first quarter earnings and sales as it drew more customers online and its Kindle electronic reader gained momentum.

Its shares rose two percent in after-hours trading.

The global online retailer, which sells everything from books to auto parts on the Internet, increased revenue an unexpectedly strong 18 percent in a sluggish global economy, which some analysts attributed to successful promotions.

It posted a 21 percent sales gain in North America.

Chief Executive Jeff Bezos said sales of the company's Kindle electronic reader had exceeded our most optimistic expectations.

The global online retailer said first-quarter net income rose 24 percent to $177 million, or 41 cents per share, from $143 million, or 34 cents per share, a year earlier.

Analysts, on average, had been expecting earnings of 31 cents, according to Reuters Estimates.

Revenue jumped 18 percent to $4.89 billion, the company said, but a stronger U.S. dollar tempered the boost from international sales. Wall Street had been expecting revenue of $4.75 billion.

My first impression is it's incredibly impressive, said Steve Weinstein at Pacific Crest Securities, noting that the company's U.S. business was growing faster than the overall e-commerce market. It's an incredible feat.

It tells you how well they're executing and winning business with customers and increasing share of wallet with their consumers.

Once criticized for spending on technology investments and putting sales ahead of profits, Amazon is now praised by Wall Street analysts who laud its ability to attract consumers in the midst of a recession. But a run-up in shares has made its valuation soar, scaring off potential investors.

International sales in the quarter rose 15 percent, but on a currency neutral basis that figure rose 28 percent.

Operating margins as a percentage of sales were better than the year-ago quarter, and improved sequentially from the fourth quarter.

Amazon said it expects second-quarter revenue to range between $4.3 billion and $4.75 billion on operating profit of $110 million to $190 million, a decline between 12 percent and 49 percent. In the year-ago second quarter, results were boosted by a one-time gain.

The outlook includes some $90 million for stock-based compensation and amortization, and assumes no acquisitions.

Shares rose more than 2 percent in extended trade to $82.45 after closing at $80.61, up nearly 2 percent, on the Nasdaq.

(Reporting by Alexandria Sage; editing by Edwin Chan and Carol Bishopric)