The Lord's Resistance Army was originally a Ugandan rebel group supported by Sudan that fought in the Ugandan civil war of the 1980s. It was active mostly within Uganda, but was eventually pushed out of the country completely. Since then, the Lord's Resistance Army has been operating in the remote corners of the Democratic Republic of the Congo, South Sudan and the Central African Republic. Ugandan, South Sudanese and Congolese forces have all attempted to find the rebels and destroy them, but while the military forces have weakened the rebels over years of tracking, a core group of the Lord's Resistance Army remains active. Though the rebels do not pose a strategic threat to the government or economy, they do pose a humanitarian threat by attacking villages, looting for food or medicine and abducting children to join the ranks of the rebel army. Sustaining themselves, mainly by securing access to food, has become their core objective. During harvesting seasons, rebels often settle near population centers where they can gather food off the fields. Over the past few years, the rebels have focused their activity in two areas: the northeastern corner of the Democratic Republic of the Congo (in and around Garamba National Park) and on both sides of the Congo's border with the Central African Republic. These areas are huge and the Lord's Resistance Army only numbers between 300 and 400 fighters, according to very rough estimates, making the group extremely difficult to locate in the vast Central African jungles. Additionally, the equatorial rainforests are very thick, restricting mobility on the ground as well as observation from the air. The vegetation also limits the effectiveness of weapons such as heavy machine guns, snipers or direct fire artillery. Long-range mobility in these regions is mostly achieved by planes, if airfields are present, or by helicopters. Convoys by road are slow and inefficient in efforts to track and isolate small rebel elements that move through the thick foliage on foot. Mobility is further restricted by a network of small rivers that cut through the jungle in every direction and cause flooding during the rainy season, which makes the status of roads unpredictable. The vast terrain in combination with the divided political borders and lack of infrastructure has provided the rebels with shelter for over a decade. Even with international help, tracking down the Lord's Resistance Army rebels is complicated by these persistent geographic constraints.