WASHINGTON -

Americans bought fewer previously owned homes in March, a reminder that the housing market remains weak.

The National Association of Realtors said Thursday that home sales fell 2.6 percent last month to a seasonally adjusted annual rate of 4.48 million. That followed a revised 4.6 million sold in February.

A mild winter may have encouraged more people to buy earlier, essentially stealing sales from March.

More purchases in January and February made this the best winter for sales in five years. The increase offered some encouragement ahead of the spring-buying season.

Even with the gains, sales remain far below the six million per year that economists equate with healthy markets. And the weaker March figures suggest that any momentum from the winter has stalled, said Dan Greenhaus, chief global strategist at BTIG, in New York.

There were some signs of modest improvement.

First-time buyers, who are critical to a housing recovery, rose to 33 percent of all purchases last month. In healthy markets, they make up at least 40 percent.

The supply of homes on the market fell 1.3 percent last month to 2.37 million. And the number of homes at risk of foreclosures declined.