For months, the day laborers had decontaminated homes that survived the Los Angeles wildfires. Sweating in masks and protective suits, they vacuumed toxic soot and ash, wiped down books and framed photos, and disposed of clothes and furniture that could not be salvaged.

One morning last month, they crammed into a small job center in Pasadena, Calif., ready for more work. But on this day, the situation felt too dangerous.

It wasn’t the contaminants or toxic fumes. Outside the Winchell’s Donut House just blocks away, federal immigration agents had detained six people.

The day laborers went home instead of heading to their job sites.

“They’re living in fear,” said Jose Madera, the director of the Pasadena Community Job Center, which earlier this year helped train about 40 immigrant workers in fire cleanup. “They don’t know what can happen if they go to work — are they going to come back?”

Immigrant workers are playing a crucial role in the recovery of Pasadena, Altadena and Pacific Palisades after the devastating fires in January. They have hauled debris, cleaned smoke-affected homes and in some cases begun reconstruction in the months since the Eaton and Palisades fires burned more than 16,000 buildings in the region.