SYDNEY (AP) — An Australian nurse who says he was forced by Islamic State militants to work as a medic in Syria will appear in a Sydney court on Saturday on terrorism-related charges, police said.

Adam Brookman, 39, was arrested on arrival at Sydney International Airport on Friday night on a Victoria state warrant relating to his alleged involvement in the conflict in Syria, Australian Federal Police said in a statement.

He will appear in the Parramatta Local Court on Saturday, where members of the Melbourne city Joint Counter Terrorism Team will seek his extradition to Victoria.

Police did not detail his charges.

Brookman surrendered to Turkish officials in Turkey on Tuesday. He voluntarily flew back to Australia with a police escort.

Brookman, a Muslim convert and father of five children who live in Melbourne, told Fairfax Media in May that he went to Syria last year to do humanitarian work for civilians caught in the war. He said he was innocent of any crime.

Brookman said he was forced to join Islamic State militants after being injured in an airstrike and taken to a hospital controlled by the group.

"After I recovered, they wouldn't let me leave," he told Fairfax.

He won the militants' trust by working as a medic and was able to escape to Turkey in December.

Brookman told Fairfax that he opposed the violent and extreme actions of the militants, including the beheading of their captives.

"Of course there will be an investigation. That is fine. Hopefully things don't look that bad," Brookman told Fairfax.

It is not clear whether Brookman was still in Syria on Dec. 4, when Australia made a presence in the Islamic State stronghold of al-Raqqa province in Syria a crime punishable by 10 years in prison. If charged, the onus would be on Brookman to prove he had a legitimate reason to be in the terrorist hotspot.