One of the most prominent immigration rights activists in the US, who revealed in 2011 that he was an undocumented immigrant, has been detained and later released by authorities at a Texas airport after visiting a city bordering Mexico.

Jose Antonio Vargas was in McAllen as part of a campaign to highlight the plight of tens of thousands of migrant children who have been held in detention centres for crossing into the country without legal documentation.

The US Border Patrol said agents apprehended Vargas "after he stated that he was in the country illegally".

He was later released on his own recognizance and provided with a notice to appear before an immigration judge.

Vargas, 33, who has lived for years in the US without proper papers, has made himself a focal point of debate about immigration with frequent media appearances and testimony last year before a US Senate committee.

He has travelled extensively throughout the country without any US government-issued identification and using his Philippines passport, which does not contain a visa for staying in the country.

Although he had not ventured outside the US, the New York Times reported that "because of McAllen’s proximity to the border, all airports and roadways in this region have Border Patrol checkpoints".

Vargas, a Pulitzer-Prize winning journalist, was brought from the Philippines as a child to live with his grandparents in California.

US authorities are currently dealing with a surge of unaccompanied and undocumented children coming over the country's southern borders with Mexico.

Over 57,000 have illegally entered the US since October, the majority arriving in Texas, according to official data.

They are mostly from central America, fleeing poverty and violence.

Campaigning group Define American said that Vargas has also created dozens of jobs through his activist work.

It said Vargas had come to McAllen to join other lobby groups "to stand in solidarity with and humanize the stories of the children and families fleeing the most dangerous regions of Central America".

Source: Agencies