SAN DIEGO (AP) -- Southern California home prices neared a five-year high in April as sales accelerated in more expensive markets, a research firm said Tuesday.

The median price for new and existing homes in the six-county region hit $357,000 last month, rising $11,500 during April alone and up 23.1 percent from the same period last year. It marked the 13th straight month of annual gains and the highest median price since June 2008, when it was $360,000.

Sales were unusually brisk for an April, growing 9.5 percent from last year to more than 21,415 homes It was the highest April sales tally since 2006.

A healthier economy is enticing buyers, and rising prices are encouraging sellers, fueling sales in mid- to high-end markets, said John Walsh, DataQuick's president.

Sales between $300,000 and $800,000 rose 35.4 percent from last year while sales above $800,000 climbed 51.4 percent. On the low end of the market, sales below $300,000 slid 21.1 percent.

Investor purchases and all-cash buyers stayed near all-time highs, the San Diego-based research firm said.

Absentee buyers - mostly investors and second-home purchasers - bought 30.2 percent of the region's homes in April, up from 28.4 percent a year earlier. Cash buyers accounted for 33.5 percent of purchases, up from 32.2 percent.

All six counties posted double-digit price increases in percentage terms and strong sales. Orange, the most expensive county with a median sales price of $535,000, tied with Los Angeles for the biggest price gain in percentage terms and had the strongest sales increase.

Foreclosed homes were a smaller part of the sales mix, lifting the overall median price because they tend to sell at steep discounts. Homes that were foreclosed upon during the previous year accounted for 12.4 percent of existing home sales, down from 28.8 percent a year earlier and from 56.7 percent in February 2009.