One of the Senate’s most vocal opponents of granting undocumented immigrants a path to legal status has filed an amendment that would elevate being in the United States illegally from a civil violation to a federal crime.

Sen. Jeff Sessions, a Republican from Alabama, filed the amendment to a sweeping bipartisan immigration reform bill that is under debate on the Senate floor.

It is based on a measure that a House committee passed on Tuesday. That bill is the Strengthen and Fortify Enforcement (SAFE) Act, which gives state and local police the power to act as quasi-immigration agents and arrest immigrants who are in the country illegally. It also allows states to enact their own immigration laws, such as Arizona, for instance, did a few years ago.

The Senate bill, drafted by the so-called “Gang of Eight,” four Democrats and four Republicans, at its core tightens border security, expands guest worker visas and provides a pathway to legal status to many of the nation’s 11 million undocumented immigrants.

“The Gang of Eight plan not only would effectively create an immediate amnesty for those here illegally today but a permanent de facto amnesty for future illegal aliens who arrive tomorrow,” Sessions said.

“The SAFE Act moves in the opposite direction,” Sessions said in a statement. “It empowers our immigration officers with the tools and resources they need to ensure future lawfulness in our immigration system. The House Judiciary Committee worked with the law enforcement community to produce this legislation—the Gang of Eight worked with the special interests to craft provisions to further handcuff law enforcement from doing their jobs.”

Opponents of the SAFE Act say it is wrong to treat undocumented immigrants as criminals, and that many come to flee poverty or civil strife at home, and to contribute to the United States. They say that making police quasi-immigration agents will make communities less safe by dissuading immigrants from contacting law enforcement agencies when they are victims of, or witnesses to, a crime.

The House Judiciary Committee approved the bill, which was sponsored by Rep. Trey Gowdy, a Republican from South Carolina, late Tuesday night on a party-line vote of 20 to 15.

Unlike the Senate, the House is approaching immigration reform in a piecemeal way, with separate bills that address various aspects of the issue.

Democrats called the bill a dangerous retread of a similarly tough enforcement measure that sparked mass protests around the country in 2006. Reading the SAFE Act bill, "you would think there are 11 million criminals in the United States," said Rep. Luis Gutierrez, D-Ill, one of Congress’s most vocal proponents for a measure that would provide a pathway to legalization for undocumented immigrants.

Among other amendments introduced in the Senate on immigration were several by Ted Cruz, a Republican from Texas, that would bolster border security, increase high-skilled temporary worker visas five-fold, streamline the legal immigration process, and deny welfare and citizenship to undocumented immigrants who obtain a provisional legal status under the current Senate immigration reform bill.

Elizabeth Llorente can be reached elizabeth.llorente@foxnewslatino.com

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