PORTSMOUTH, N.H. — A Connecticut-based nuclear submarine is going to spend the next 20 months at Maine's Portsmouth Naval Shipyard while the vessel undergoes maintenance and upgrades.

The fast attack submarine USS Miami arrived in the Maine-New Hampshire area on Thursday after operating five months in Europe.

The Miami is based in Groton.

Foster's Daily Democrat says the Miami has been traveling between ports in Europe and across the Mediterranean conducting maritime security operations.

The shipyard will perform most of the repair work, but crew members are also going to be working on the vessel and training.