It came as no surprise that the GOP candidates running in the 2016 presidential election spent an ample amount of time discussing immigration reform, an ongoing hot button issue in the national discourse, during the first Republican primary debate on Thursday.

Most of the candidates reaffirmed their stance on immigration when the topic came up at the Fox News debate.

When asked why he no longer supports a pathway to citizenship, Wisconsin Gov. Scott Walker reasoned that his views on immigration shifted once he "actually listened to the American people," reports CBS News.

Walker then outlined his immigration policy, saying he would "secure the border, enforce the law, no amnesty, and go forward with a legal immigration system that gives priority to American working families and wages."

Florida Sen. Marco Rubio chimed in, saying that "the evidence is now clear that the majority of people coming across the border are not from Mexico. They're coming from Guatemala, El Salvador, Honduras."

However, a report by the Pew Research Center, states that undocumented immigrants make up 3.5 percent of the U.S. population, while about 52 percent of that population come from Mexico.

Moderator Chris Wallace asked Donald Trump, the current GOP front-runner in the race, for evidence to prove his assertion that the Mexican government is sending rapists and criminal migrants to the States. In response, Trump defended his accusation, saying that he received this information after speaking with Border Patrol agents.

"I was at the border last week. Border patrol people that I deal with, that I talk to, they say this is what's happening because our leaders are stupid, our politicians are stupid, and the Mexican government is much smarter...they send the bad ones over because they don't want to take care of them," Trump said. "That's what's happening, whether you like it or not."

On the other hand, a 2010 American Community Survey (ACS) has proven that Trump's assertion about the criminality of Mexican immigrants is not true. According to the report, immigrants are less likely than native-born citizens to be incarcerated.

Trump also stood firm on his vow to build a wall along the U.S.-Mexico border, notes Fox News.

Former Florida Gov. Jeb Bush, on the other hand, took a softer approach on the issue and defended the comments he made last year when he called illegal immigration an "act of love."

"I believe that the great majority of people coming here illegally have no other option. They want to provide for their family. But we need to control our border," he said.

Bush added that a comprehensive solution is needed, including a "path to earned legal status," which he said is not "amnesty."

Shortly thereafter, Texas Sen. Ted Cruz jumped in accusing some of his opponents of supporting "amnesty."