CHARLESTON, S.C. -- Former House speaker Newt Gingrich offered a detailed explanation at a town hall here Monday evening on how he would confront illegal immigration if he wins the White House.

Gingrich, who continued to attract overflow crowds to his surging presidential campaign, appeared at a town hall hosted by U.S. Rep Tim Scott (R-S.C.). He pledged that, if he won, he would send half the employees of the Department of Homeland Security to the states along the Mexican border. He promised to secure the border by January 2014, to make English the nation’s official language and to make some illegal immigrants pay a penalty in exchange for a path to legal residency.

Gingrich’s extended explanation of his position reflected the fire he has received from two opponents over his remarks at a televised debate last week, in which he supported establishing a path to legal residency — but not citizenship — for longstanding illegal immigrants who have roots in their communities.

Both Mitt Romney, the former Massachusetts governor and Gingrich’s chief rival for the nomination, and Rep. Michele Bachmann, have suggested that Gingrich supports a path to amnesty for illegal immigrants. Gingrich has said repeatedly that he does not support amnesty, and on Monday he accused his rivals of not being truthful on the subject.

But Gingrich spent several minutes on the subject Monday, a reflection of the importance of the issue to Republican primary voters — particularly in South Carolina, a crucial early state with a conservative GOP electorate, where Gingrich is investing heavily in organization and staff.

“Several of my friends have been running around saying things that are not true,” he said. “The fact is, I don’t believe you’ll ever pass a bill which requires us to hunt down every person who’s been here for a quarter-century. There’s a humane, orderly way to do this.”

Gingrich said all environmental impact requirements and other federal regulations should be waived to complete a border fence. He said any illegal immigrants affiliated with criminal gangs should be deported immediately — “If you are not an American citizen, you are not automatically entitled to all the defenses of the American justice system.”

The line generated some of the most enthusiastic applause of the evening. But Gingrich got a round of applause for his “humane” line, to.

Gingrich was kicking off a three-day swing through South Carolina, with stops planned Tuesday and Wednesday in Hilton Head and Greenville.