Last year Immigration and Customs Enforcement rounded up 193,000 foreign nationals with criminal convictions and charges but deported only 125,000 of them while releasing 68,000, Fox News reported.

The Center for Immigration Studies obtained and poured through the ICE documents and released the information in its Catch and Release: Interior Immigration Enforcement In 2013 report.

The group, which is based out of Washington, D.C. and advocates for stricter immigration enforcement, found that ICE encountered 722,000 illegal immigrants with criminal convictions in 2013 but charged 195,000 of them -- roughly 25 percent, according to the report.

The report revealed that ICE found most of the immigrants after local authorities had already arrested them.

Jessica Vaughan, the study's author, said in a statement that she blamed President Barack Obama's administration for its prosecutorial discretion policies in releasing the "ciminal aliens" rather than deporting them.

"The Obama administration's deliberate obstruction of immigration enforcement, in which tens of thousands of criminal aliens are released instead of removed, is threatening the well-being of American communities," Vaughan said. "It's not a matter of if, but how many families will suffer harm as a result."

The report also revealed that more than 870,000 illegal immigrants have been marked for deportation on ICE's docket, but the agency has not done anything yet.

"Under current policies, an alien's family relationships, political consideration, attention from advocacy groups, and other factors not related to public safety can trump even serious criminal convictions and result in the termination of a deportation case," according to the study.

The report called for an increase in detention capacity because it found that roughly 75 percent of ICE detainees in 2013 had criminal convictions "so serious that the detention was required by statute."

ICE accused CIS of misrepresenting the collected data, claiming that a number of the cases could have represented minor offenses. It also corrected the number of removed "convicted criminals" in 2013 to 216,000.

An ICE spokeswoman told Fox in a statement that the agency is committed to finding and deporting illegal immigrants with criminal records and that their removal rate has increased.

"ICE is focused on the removal of criminal aliens," the spokeswoman said. "The percentage of criminals removed continues to rise. Nearly 60 percent of ICE's total removal had been previously convicted of a criminal offense, and that number rises to 82 percent for individuals removed from the interior of the U.S. The removal of criminal individuals is and will remain ICE's highest priority."