President Obama became the first sitting U.S. president to a visit a federal prison on Thursday when he took a tour through Oklahoma's El Reno Correctional Institution in Oklahoma.

During his visit, the president met with both law enforcement officials and six prisoners at the medium-security prison, reports The New York Times. The trip was also recorded by Vice as part of an HBO documentary slated to air later this year.

"I think we have a tendency sometimes to almost take for granted or think it's normal that so many young people end up in our criminal justice system. It's not normal. It's not what happens in other countries. What is normal is teenagers doing stupid things," Obama said after touring the facility, reports CNN.

Obama, who is pushing to reform the prison and sentencing system, touched upon the issue of mass incarceration, saying, "What is normal is young people make mistakes," and that the only difference between the inmates and most Americans are "resources," and "social support structures."

He added that "This is part of our effort to highlight both the challenges and opportunities we face with respect to the criminal justice system."

The President went on to say that he hopes reform on the federal level will trickle down to the state level.

"My goal is that we start seeing some improvements at the federal level and that we're then able to see states across the country pick up the baton, and there are already some states that leading the way in both sentencing reform as well as prison reform and make sure that we're seeing what works and build off that," Obama said Thursday.

Both Democrats and Republicans, including 2016 contender Sen. Rand Paul, have rallied behind reform of the criminal justice system. The influx in the prison system stems from former President Bill Clinton federal sentencing rules.

As a result, the U.S. prison complex has grown to house 25 percent of the world's prisoners although the U.S. comprises only 5 percent of the world's total population. This has disproportionately hurt communities of color since almost 1-in-12 black men ages 25-54 are imprisoned, compared to 1-in-60 non-black men in that age group.