The Navy says the final journey of a fire-damaged submarine to the scrapyard should take less than two months.

The former USS Miami was towed away from Portsmouth Naval Shipyard on Friday after workers completed the inactivation process, which included removing nuclear material.

Shipyard spokeswoman Danna Eddy said it will likely take about seven weeks for the submarine to be towed to Puget Sound Naval Shipyard in Washington state for dismantling.

A former shipyard worker is serving a 17-year prison sentence for setting the fire in May 2012.

The Navy originally intended to return the Los Angeles-class attack submarine to the fleet after extensive repairs. But it decided to scrap the sub when estimated repair costs grew to upward of $700 million.