Latino immigrants working in a Los Angeles grocery store (file photo)

A Washington-based institute says half of the workforce in Los Angeles, California, is made up of immigrants, many of whom are unskilled and speak little English.

The Migration Policy Institute (MPI) reports the immigrant workforce lacks the skills needed to replace a large bloc of U.S. workers nearing retirement age, known as the baby boomer generation.

The group's study also says Los Angeles is at the leading edge of a demographic trend taking place across the United States.

MPI reports that more than one-third of the 9.9 million people who live in Los Angeles County are immigrants.

It recommends more resources be devoted to the integration of immigrants into U.S. classrooms, workplaces and civic life.

The institute says Los Angeles can serve as a policy laboratory for other U.S. communities.