In the spring of 2001, ethnic Albanian insurgents calling themselves the National Liberation Army (some of whom were former members of the Kosovo Liberation Army) took up arms in the north and northwest of the Republic of Macedonia. They demanded that the constitution be rewritten to enshrine certain Albanian minority interests such as language rights. The guerillas received support from Albanians in NATO-controlled Kosovo and Albanian guerrillas in the demilitarized zone between Kosovo and the rest of Serbia. The fighting was concentrated in and around Tetovo, the fifth largest city in the country, and in the wider regions of Skopje, the capital, and Kumanovo, the third largest city.