In July 1779, British general Francis McLean captured Castine and built Fort George on the Bagaduce Peninsula on the eastern side of Penobscot Bay. The Commonwealth of Massachusetts sent the Penobscot Expedition led by Massachusetts general Solomon Lovell and Continental Navy captain Dudley Saltonstall. The Americans failed to dislodge the British during a 21-day siege and were routed by the arrival of British reinforcements. The Royal Navy blocked an escape by sea so the Patriots burned their ships near present-day Bangor and walked home. Maine was unable to repel the British threat despite a reorganized defense and the imposition of martial law in selected areas. Some of the most easterly towns tried to become neutral.