Some 276 "sanctuary cities," nearly 50 percent more than previously revealed, released over 8,000 illegal immigrants with criminal records or facing charges free despite federal requests that they be turned over to Immigration and Customs Enforcement for deportation, according to an explosive new report.

The Center for Immigration Studies, revealing new numbers it received under the Freedom of Information Act, said that those releases from cities that ignored federal demands came over just eight months and are just part of an even larger release of 17,000 illegals with criminal records.

RELATED: Map -- Over 200 'sanctuary cities' in 32 states and D.C.

Author Jessica M. Vaughan, director of policy Studies for the center, also reported that many of those illegals have been rearrested after their release and charged with nearly 7,500 new charges, including child sex abuse.

Francisco Sanchez, right, is lead into the courtroom for his arraignment in the shooting death of 32-year-old Kathryn Steinle. (Michael Macor/ San Francisco Chronicle via AP, Pool)

The report, titled "Ignoring Detainers, Endangering Communities State/local agencies release criminals rather than obey law," provided to Secrets, is expected to fuel U.S. anger over sanctuary cities and the murder by one freed illegal of a San Francisco woman earlier this month.

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"The Obama administration has given sanctuaries free rein to ignore detainers by ending the successful Secure Communities program and replacing it with the Priority Enforcement Program. This new program explicitly allows local agencies to disregard ICE notifications of deportable aliens in their custody by replacing detainers with 'requests for notification,'" wrote Vaughan.

"The only truly effective and lasting solution is for Congress to spell out in federal law that local law enforcement agencies must cooperate with ICE by complying with all detainers or face sanctions in the form of disqualification from certain kinds of federal funding," she added.

The new federal documents show that there are at least 276 sanctuary cities, more than the 200 previously believed, and are in 43 states, also more than previously revealed. Instead of turning illegal immigrants facing criminal charges over to ICE under its "detainer" rule, the sanctuaries simply ignore the request in many cases let the illegals go.

RELATED: No to 'sanctuary cities' by 2-1 margin, public says

Many of those released had more than one ICE "detainer" request.

The majority, 5,132, had past criminal records, like Juan Francisco Lopez-Sanchez, the illegal previously deported five times and now charged with murdering 32-year-old Kate Steinle. Of those, 2,984 had a prior felony conviction or charge.

And, 1,867 offenders who were released were re-arrested, accumulating 7,491 new charges, including child sex abuse. Vaughan's report found that 10 percent of the new charges involved dangerous drugs and seven percent were for driving under the influence of alcohol.

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Read the report below.

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com.