again reformed the militia, renaming it the Massachusetts State Guard due to the events of World War I. Anticipating a possible German invasion or other emergency and lacking the National Guard due to deployment, many states created and trained state guard units. After the Halifax Explosion in Nova Scotia in 1917, a medical detachment from the Massachusetts State Guard was among the first units to arrive and offer aid. As an expression of gratitude for the aid provided by the Boston Red Cross and the Massachusetts State Guard, the city of Halifax sent the city of Boston a Christmas tree, a gift which was revived in the form of an annual tradition conducted by the province of Nova Scotia in 1971 which continues to this day. During the 1918 flu pandemic, the Massachusetts State Guard operated nine hospitals to treat civilians. The State Guard was activated during World War II and served as a light infantry division until deactivation in February 1947. During World War II, the Massachusetts State Guard, training alongside other guardsmen from other states in New England, practiced capturing soldiers from Fort Devens (then Camp Devens) who would pose as enemy paratroopers, and "practiced using grenades, digging trenches, charging across fields with their shotguns, making incendiary and smoke bombs and Molotov cocktails, and creating roadblocks." The guard also maintained a Flying Column as a quick reaction force to help compensate for the National Guard's absence, and were active for the duration of the war. In addition to the combat division, the Massachusetts State Guard operated the Women's Defense Force (WDC), a unit made up of women who were responsible for medical, firefighting, air raid alert, transportation, canteen, and communications services. During the Vietnam War, the Massachusetts State Guard was reorganized and trained to be able to replace the 26th Infantry Division of the Massachusetts National Guard in the event that the guard unit was deployed. 21st Century The Guard was renamed the Massachusetts Military Reserve in June 1994; the State Guard name was restored during the group's reorganization after the September 11, 2001 attacks. The Massachusetts State Defense Force went on inactive status in February 2008. However, due to the need for additional assistance in emergency management, and the shortage of state resources due to frequent deployments of the National Guard, the Massachusetts State Defense Force was reactivated on May 31, 2011. The State Defense force was