In 2002, Burundi had an army with an estimated 40,000 personnel. The troops included seven infantry battalions, two armed squadrons, one engineer battalion, one air defense battery, and independent infantry companies. Paramilitary gendarmerie numbered around 5,500. Opposition forces included up to 16,000 troops in the FDD (Forces for the Defense of Democracy) and an estimated 2,000–3,000 in the Forces for National Liberation. The defense budget in 2001 was $36.9 million or5.3% of GDP.