Federal Immigration officials arrested at least 100 illegal immigrants this week as part of a sting operation that began on Wednesday, reports the San Gabriel Valley Tribune.

On Wednesday, U.S. Immigration and Customs Enforcement (ICE) officials said the operation targeted “individuals who pose a threat to national security, public safety and border security.”

“This means that, ideally, we are working with local police and county jails to identify public safety threats in their custody, who are also in the country illegally, for deportation,” ICE officials said in a statement.

The City of Los Angeles has done little to help carry out their mission, being that it fancies itself an illegal "sanctuary city," which goes as far as to bar police from checking a criminal's immigration status upon arrest. ICE officials said such “uncooperative jurisdictions” have made their jobs harder, forcing them to “focus additional resources to conduct at-large arrests in the community, putting officers, the general public and the aliens at risk and increasing the incidents of collateral arrests.”

In retaliation for the lack of cooperation, ICE officials will no longer follow priority criteria for arrests, so “all of those in violation of the immigration laws may be subject to immigration arrest, detention and, if found removable by final order, removal from the United States.”

Since Sunday, more than 100 illegals were arrested in seven different Southern California counties. ICE officials hope another 300 will be added to the count by the time the operation finishes. Speaking with The Wall Street Journal, ICE officials said those detained have serious crimes on their record or suspected of serious crimes.

The operations were conducted in Southern California, including Los Angeles, Orange, Riverside, San Bernardino, Ventura, Santa Barbara, and San Luis Obispo counties.

Following Attorney General Jeff Session's threat against "sanctuary cities" like Los Angeles, Mayor Eric Garcetti said it was a "myth that we don’t collaborate or cooperate with federal officials.”