To his Long Island family, Marcos Alonso Zea was an honor student, aspiring teacher and good Catholic.
To leaders of a mosque he visited, he was a young convert in a traditional gown who called himself "Ali."
To the FBI, he was a terrorist in the making, intent on joining al-Qaida and waging "violent jihad."
Zea, 25, grew up in Brentwood, raised by immigrants: a mother from Guatemala, Sandra; and a father from Colombia, Alvaro. The family, including Zea and several siblings, regularly attended St. Anne Catholic Church, his parents said.
After graduating from Brentwood High School in 2006, Zea took classes at Dowling College and Suffolk County Community College's Brentwood campus, where he earned a liberal arts degree in August 2011, officials said.
"He wanted to be somebody important in life," Sandra Zea said Friday in Spanish, referring to her son's teaching aspirations.
He completed a teaching course last December, she said, proudly displaying the certificate during an interview at the family's tidy home in a working-class neighborhood of Brentwood.
But Marcos Zea was also increasingly fascinated with Islam. Prosecutors say he converted in 2009.
A few years ago, he began visiting the Masjid Darul Qur'an mosque in Bay Shore, according to mosque leaders. One of the few Latinos, he would show up once or twice a month for the main prayers of the week, on Fridays.
Muhammad A. Jabbar, the mosque's imam, said Zea would ask "difficult" questions about the religion and its rituals, and seemed to adopt a "hard line" approach adapted from books and websites.
Jabbar, however, said he never saw any indication that Rea was embracing extremist views.
"He was kind of shy and quiet," said Roshan A. Shaikh, the mosque's president.
Still, the leaders noted that Zea had befriended Justin Kaliebe, 18, who also occasionally attended the mosque. Kaliebe, of Babylon and Bay Shore, pleaded guilty in February to charges of attempting to provide material support to terrorists and to a foreign terrorist organization.
Zea had asked if Kaliebe could sleep in the mosque because he was having trouble with his family at home, Shaikh recalled. The request was denied.