WASHINGTON — Unemployment among Hispanics, and particularly Hispanic immigrants, jumped in the past year, wiping out many of their economic gains, according to a report released Wednesday by the Pew Hispanic Center.

Amid an extended housing and construction slump that has claimed hundreds of thousands of jobs, the Pew findings alarmed Hispanic leaders. They also indicated aggressive new enforcement raids by immigration officials might be having an effect.

The report shows that unemployment among all Hispanics is higher than the general population. Among Hispanic immigrants, it is higher still, and within that group, Mexican immigrants and recent arrivals are suffering some of the largest increases in joblessness.

"It's striking indeed, especially for foreign workers and the Mexican-born," said Rakesh Kochhar, associate director for research at the Pew Hispanic Center, a nonprofit, nonpartisan think tank.

General unemployment rose to 5 percent in the first quarter of 2008 on a nonadjusted basis. But among Hispanics, it reached 7.3 percent; among Hispanics who are immigrants, 7.5 percent; and among immigrants from Mexico, 8.4 percent. Immigrants who arrived in 2000 or later were hardest hit, with 9.3 percent joblessness.

The jobless gap between Hispanics and non-Hispanics has begun to widen after narrowing to historic lows. At the end of 2006, the gap had narrowed to 0.5 percentage points, with unemployment rates of 4.9 percent for Hispanics and 4.4 percent for non-Hispanics, on a seasonally adjusted basis.

By the beginning of this year, the gap had grown to nearly 2 points, with unemployment rates of 6.5 percent for Hispanics and 4.7 percent for non-Hispanics, on a seasonally adjusted basis. The report is based on the most recent data from the U.S. Bureau of Labor Statistics and the federal Census Bureau.

The increasing gap and rising joblessness worried Hispanic leaders. "These numbers highlight how much the Latino community is being disproportionately affected by the current economic crisis," said Rep. Joe Baca, D-Calif., leader of the Congressional Hispanic Caucus. "The Latino community not only has to contend with our weakened economy but also with an increasingly negative immigration debate — neither of which brings good news for Latino unemployment rates."

The Pew report attributes the majority of job losses to the ongoing slump in the construction industry. But Kochhar acknowledged that immigration enforcement efforts also might be a factor. "Economic downturns tend to reduce immigration flows, ... but we can't point to a cause and effect," he said.

Hispanics make up 14.2 percent of the U.S. labor force and just more than half of working-age Hispanics are immigrants, the report said. While Pew researchers were not able to identify the legal status of immigrant workers, they estimate illegal immigrants account for 5 percent of the U.S. labor force.

Most illegal immigrants come from Latin America, and the report noted that Mexicans account for about 55 percent of the total.

Amid a downturn in the construction sector, the report found 90 percent of Hispanic job losses in construction were among immigrants.

And while Hispanic wages fell across the board, Hispanic construction workers experienced the sharpest drop, earning less now than they did in the first quarter of 2006.

Immigration and Customs Enforcement officials said they believed their raids are prompting employers to think twice about hiring illegal immigrants. "We believe that our enforcement efforts are having an impact," said ICE spokeswoman Kelly Nantel, adding raids have resulted in improved compliance by businesses.