From AP - News National/International -

Journalist, Activist Jose Antonio Vargas Detained By US Border Patrol

Jose Antonio Vargas

Pulitzer Prize-winning journalist, immigration rights activist and self-declared undocumented immigrant Jose Antonio Vargas becomes emotional as he testifies about comprehensive immigration reform during a hearing of the Senate Judiciary Committee on Capitol Hill in Washington, Wednesday, Feb. 13, 2013. (Susan Walsh/AP)

A prominent immigration activist and Pulitzer Prize-winning journalist who has lived and worked in the U.S. without legal documentation for years has been detained by U.S. Border Patrol agents at a South Texas airport.

Border Patrol spokesman Omar Zamora says Jose Antonio Vargas was in custody Tuesday morning, but he had no other details.

Vargas had been in the border city of McAllen for several days as part of a vigil drawing attention to the plight of unaccompanied immigrant children and families coming into the U.S. illegally.

On Tuesday morning, Vargas tweeted: "About to go thru security at McAllen Airport. I don't know what's going to happen.''

At the McAllen airport, Border Patrol agents stand beside Transportation Security Administration agents checking documentation, even for domestic flights.