Federal ICE agents conduct a raid at a southern California farm reportedly growing marijuana illegally, and are met with protesters. (Credit: KABC LA)

As word spread among Catholics that immigration agents were visiting places of worship to carry out deportations, the pews inside the Cathedral of Our Lady of the Angels Catholic Church in downtown Los Angeles became less and less crowded.

Federal immigration agents seeking to detain a Honduran landscaper chased him into a Southern California surgical center and quickly found themselves in a tense standoff as clinic staff demanded to see identification and a warrant.

As Trump tries to carry out mass deportation, ICE arrests are up. Compare his record to Obama's, who earned critical reputation as "deporter in chief"

California has six privately operated immigration detention centers. Two of these — Golden State Annex in McFarland and Mesa Verde ICE Processing Center in Bakersfield — are also located in Kern County and run by The Geo Group, another private prison operator.

A confrontation erupted Thursday between protesters and federal officials carrying out a raid on a Southern California farm.

ICE can put in a civil detainer requesting that departments give them a heads-up when a suspect will be released. A California law allows departments the choice to honor the request or not.

Officers appeared to use crowd control munitions and tear gas against protesters. The F.B.I. said it was searching for a person who appeared to fire a pistol at officers.

Demonstrators in San Francisco, Calif., attempted to block ICE agents from moving detainees from an immigration courthouse to a waiting van. KNTV's Thom Jensen reports.