SACRAMENTO (CBS13) — More than a dozen of undocumented immigrants are behind bars after a new crackdown across Northern California by federal immigration agents.

Federal officials are in the midst of a new immigration operation in that attorney Douglas Lehrman says, could be depriving his clients’ of their right to due process.

“The applicant we saw had a denied application about six months, a year ago and didn’t refile. They may have had some information about the person, and they knocked on their door without a warrant,” said Lehrman.

Advocates tracking the arrests say Immigration and Customs Enforcement agents have detained at least 15 people, from Sacramento to the Bay Area, accused of being in violation of immigration laws.

“It’s really instilling a lot of fear into the community,” said Carlos Montes-Ponce of Sacramento ACT.

Montes-Ponce is the voice behind a local rapid response hotline. He says he’s had a six-fold increase in calls, from family members who’ve never before had contact with federal agents.

“It’s been family members detained, leaving their homes or arriving from work,” he said.

But an ICE spokesman says the deportations are focused on “individuals who pose a threat to national security, public safety, and border security.”

The operation follows a massive sweep in LA last week. ICE agents arrested 200 immigrants. Prior to that, it went after dozens of businesses hiring undocumented workers.

Local law enforcement agencies have said they’ll no longer cooperate with ICE on sweeps.

Lehrman thinks the state’s efforts to create sanctuary protections for those here illegally, may actually be encouraging more targeted raids.

“We’re definitely being targeted because we’re a sanctuary city,” he said.