As part of a nationwide gesture to highlight crime by immigrants in sanctuary cities, the U.S. Immigration and Customs Enforcement Agency (ICE) conducted a sweep this week arresting some 487 undocumented immigrants. As the SF Chronicle reports, 181 of those arrested had no prior criminal conviction, and 27 of them were arrested in San Francisco and Santa Clara County. The offenses included everything from trespassing to assault and rape, but the single most common offense among the detained was driving under the influence.

Of the 27 people arrested in the Bay Area, 23 had prior convictions, as CBS 5 reports, with eight of those being for driving under the influence. The arrested included "a Salvadoran man apprehended in San Francisco who entered the country illegally and has previous convictions for sex with a minor under the age of 16." He had previously been in custody, presumably in San Francisco County Jail, and was released before ICE could assume custody of him.

ICE spokesman James Schwab announced the results of the sweep Thursday, and he said that Dreamers or those with active status in the Deferred Action on Childhood Arrivals program were not targeted.

ICE Acting Director Tom Homan, who announced the agency's intended crackdown back in July, issued a statement saying, "Sanctuary jurisdictions that do not honor [detention requests] or allow us access to jails and prisons are shielding criminal aliens from immigration enforcement and creating a magnet for illegal immigration... ICE’s goal is to build cooperative, respectful relationships with our law enforcement partners to help prevent dangerous criminal aliens from being released back onto the streets."

The SF Mayor's Office pushed back against ICE's statements, suggesting that this sweep was done more for political theater than anything else. "The federal government continues to harass and target members of our immigrant communities,” said the mayor's spokesperson Deirdre Hussey, per the Chronicle. "If the federal government believes there is a need to detain a serious offender, they can obtain a criminal warrant, which we will honor, as we always have."

Previously: ICE Director: 'Sanctuary Cities Are A Criminal's Best Friend'