Updated

Journalist and activist Jose Antonio Vargas, who famously revealed his undocumented status in a New York Times story three years ago, was detained Tuesday morning in the Texas border town of McAllen.

Define American, the nonprofit U.S. immigration-reform campaign he founded in 2011, announced he was under custody in a Facebook post.

Shortly before the announcement, Vargas – who is Filipino – tweeted that he was about to go through security at the airport with nothing more than a Philippine passport and a pocketbook U.S. Constitution.

“I don’t know what’s going to happen,” he tweeted.

Fox News Latino reached out to Vargas' organization and got confirmation that as of noon he was still under Border Patrol custody.

According to Define America and United We Dream, another advocacy group, Vargas, a Pulitzer Prize winner, was stopped when he attempted to board a plane to Los Angeles.

Vargas, 33, had originally traveled to the border with United We Dream staff to highlight the needs and stories of the thousands of refugee children who have fled countries in Central America in the last months. He visited a shelter and participated in a vigil in their honor.

"Mr. Vargas attempted to board a plane to Los Angeles where we are scheduled to screen our film 'Documented'.  Mr. Vargas did not make it through security at the airport," the Define America statement read.

Vargas wasn’t required to have a passport to fly internally, immigration lawyer David Leopold told FNL. But since McAllen is near the border, Border Patrol checks the IDs at airports.

"It’s just that since it’s a border area Border Patrol uses heightened patrol techniques, and hanging out in airports is one of them," Leopold said. "You see the same in other border cities, such as El Paso. Border Patrol doesn’t always check everyone, but they can set up check points," he explained.

"Vargas’ arrest underscores the need for common sense immigration enforcement which, unfortunately, the Border Patrol lacks," Leopold added.

Cristina Jimenez, Managing Director of United We Dream, said that with the arrest Border Patrol has proven to be "a rogue agency," since Vargas is a low-priority case for detention and deportation.

“We stand in solidarity with Jose Antonio and demand for his immediate release, but we must remember that there are thousands of people along the border that live with this same fear every day,” she added.

Conservative groups have called for Vargas to be detained because they claim he glorifies being in the country illegally.

According to a report by the Huffington Post, Vargas handed his password to a TSA agent, who asked him two or three questions. When Vargas told him he was traveling without a visa, he was placed in handcuffs and escorted to the McAllen border patrol station for more questioning.