Immigration and Customs Enforcement agents took several people into custody during a Basin City raid early Wednesday.
The arrests happened about 3 a.m. in the rural farming community in northern Franklin County, said Undersheriff Dan McCary.
Deputies knew the federal agents were working in that area, but Franklin County officials did not participate, McCary said.
People used social media to report seeing agents in Mesa and Basin City.
In a Facebook thread, one woman said in Spanish that her "mom's husband's brother" was arrested and he had a clean record. Another said they took people from her mother's workplace.
Carissa Cutrell with Immigration and Customs Enforcement Public Affairs had no information about the arrests.
"ICE deportation officers conduct targeted enforcement actions every day in locations across the country as part of the agency's ongoing efforts to protect the nation, uphold public safety and protect the integrity of our immigration laws and border controls," she said.
Leo Perales, vice chairman of Consejo Latino, said he's heard about agents arresting people throughout Franklin County.
The nonprofit organization issued a statement saying they are asking the Franklin County Sheriff's Office for more information. They spoke out against the local agency offering help to immigration officials.
"(S)uch cooperation and assistance will only make our area less safe, erode trust between our immigrant communities and law enforcement, and will serve to only hurt our areas agricultural industry," Consejo Latino said.
There have been similar reports of arrests in Milton-Freewater, including one at a skate park.
The raids took place the same day ICE announced it had conducted an operation to disrupt "Darknet market sites" that exchange U.S. currency for virtual currency.
The U.S. Attorney's Office for the Eastern District of Washington was among the many districts that participated, ICE said.