PORTLAND — The attorney for a Maine shipyard worker accused of setting a fire that caused $400 million in damage to a submarine said lawyers are discussing a “potential resolution” that would avoid the need for a grand jury indictment, according to court papers.

Prosecutors say Casey James Fury, 24, of Portsmouth, N.H., confessed to setting a fire in May that damaged the USS Miami at the Portsmouth Naval Shipyard. They say he also confessed to setting a second fire in June near the submarine.

In federal court documents filed this week, a judge granted a motion by Fury’s lawyer to extend the timetable for prosecutors to seek a federal indictment of Fury. The date is now Sept. 26.

Public defender David Beneman said the time was needed to allow experts to review the case.

“Defense and government counsel have been meeting to discuss this case with an eye toward potential resolution without the need for a grand jury indictment,” Beneman said in his motion. “The magnitude of the fire damage, the volume of investigatory evidence, and the forensic arson evidence in this matter are voluminous, technical, and will consume large amounts of time and resources to consolidate, produce and review.”

He added that forgoing a grand jury indictment “will save substantial national resources extending beyond just court resources.”

Fury, a painter and sand blaster, told Navy investigators that he set the fires to get out of work because he was suffering from anxiety and having problems with his ex-girlfriend.

The May blaze quickly got out of control and the steel hull trapped heat, causing superheated smoke and a stubborn fire that took more than 100 firefighters to douse.

The submarine was undergoing a 20-month overhaul at the Navy shipyard in Kittery. The fire was confined to forward compartments and did not reach the back of the submarine where the nuclear propulsion components are located.

It remains to be seen if the attack sub will be repaired or scrapped.