U.S. officials say a Somali man accused of ties to Islamist militant groups was interrogated for nearly two months aboard a U.S. warship and is now in New York to face terrorism charges.

The officials say Ahmed Abdulkadir Warsame was questioned at sea by intelligence officials for his connections to the Somalia-based al-Shabab militant group and the Yemen-based al-Qaida in the Arabian Peninsula.

They say Warsame gave up important intelligence about the relationship between the two groups.

After the interrogation was complete, U.S. officials say a separate group of interrogators came in and began to question Warsame again in a way that could be used in court. The interrogators informed Warsame of his rights under U.S. law to remain silent and to have an attorney, but officials say Warsame continue to cooperate.

The case provides insight into how the United States plans to interrogate detainees now that the Obama administration has closed the CIA's secret prison network.

U.S. officials say Ahmed Abdulkadir Warsame will now be tried in a civilian court.