New York: An American citizen from California who was radicalised by online propaganda travelled overseas to try to join a branch of the Islamic State group in Libya, US prosecutors have said.

A few days before he left in 2016, Bernard Augustine texted an unidentified relative, "If I ever get lucky enough to live in the khilafah, I'll burn my own passport, lol," according to a criminal complaint.

He made it as far as Tunisia but was detained by authorities there before he could carry out his plan, the complaint said. Augustine, 21, is from the town of Keyes in California's Central Valley. He was jailed without bail yesterday during an initial court appearance in federal court in Brooklyn. His lawyer, Samuel Jacobson, declined comment.

An examination of Augustine's laptop turned up evidence that he had been viewing Islamic State group material on the Internet, including a video showing the beheadings of Ethiopian Christians who were kidnapped in Libya, the court papers said. He also searched for "jihadology" and "how to safely join isis," it said.

In addition, Augustine viewed sermons by fiery American-born cleric Anwar al-Awlaki, a leader of al-Qaida in Yemen who was killed in 2011, the papers said. The online videos of Al-Awlaki have been cited in several US cases as being a dangerous influence on self-radicalised terrorists.

Records show Augustine took a Turkish Airlines flight from San Francisco to Tunisia via Istanbul, Turkey, using a one-way ticket. Once there he emailed the same relative in California, telling that person, "I'm not mad or mentally ill, I really truly am on a path to fight for justice," the papers said.(PTI)