PASADENA (CBSLA.com) — U.S. Immigration and Customs Enforcement agents have been going to courthouses and arresting people in America illegally, sparking outrage from prosecutors and attorneys.

They worry such tactic will discourage undocumented immigrants from appearing in court to testify as witnesses for prosecutors.

Criminal defense lawyer Octavio Chaidez said his client is among those taken into custody by ICE agents, who arrested him at the Los Angeles Superior Court in Pasadena.

He said he had just finished a criminal court appearance with his client when four agents swooped in, confirmed his name and took his client away.

“It was very shocking because it occurred inside of a courthouse, and the reason for the detention had nothing to do with that proceeding,” recalled Chaidez, who would not say if his client has a criminal history.

Chaidez said he is among many attorneys and prosecutors who worry ICE arrests at courthouses will create enough fear of deportation among witnesses or victims of crimes to affect the outcomes of cases.

“They may refuse to contact the police. They may refuse to give testimony as a witness. They may refuse to show up in court, and that affects the entire system,” the attorney explained.

The threat of deportation erodes the trust built in the non-English speaking community to persuade them to come out of the shadows and help solve crimes, Chaidez said.

“If those people are worried that their residency is going to be in jeopardy or they don’t have any status to be here in the country, then in that situation, they may not contact the police at all, even if they witnessed a very serious crime,” said the attorney, who has not seen or heard from his client since his arrest.

ICE officials said they do so only when all other options have been exhausted.