ONA), also known as the Macedonian UÇK (Albanian: UÇK Maqedonase; Macedonian: Македонска УЧК, romanized: Makedonska UČK), was an ethnic Albanian militant[13] militia that operated in the Republic of Macedonia in 2001 and was closely associated with the Kosovo Liberation Army (KLA).

[14] Following the 2001 insurgency in Macedonia, it was disarmed through the Ohrid Framework Agreement, which gave greater rights and autonomy to the state's Macedonian Albanians.

[17][18][19] After the end of the Kosovo War in 1999 with the signing of the Kumanovo agreement,[20] a 5-kilometer-wide Ground Safety Zone (GSZ) was created.

[21][22] In June 1999, a new Albanian militant insurgent group was formed under the Liberation Army of Preševo, Medveđa and Bujanovac (UÇPMB), which started training in the GSZ.

[25][26] With the signing of the Končulj Agreement in May 2001, the former KLA and UÇPMB fighters next moved to western Macedonia where the NLA was established, which fought against the Macedonian government in 2001.

"[30] The Macedonian government claimed the NLA was a terrorist organization consisting primarily of KLA fighters, lacking domestic legitimacy and seeking secession or a Greater Albania.

[37] In February, the NLA entered the village of Tanuševci and the conflict expanded to the Kumanovo, Lipkovo and Tetovo region.

[38] By the start of March, the NLA had taken effective control of a large swathe of northern and western Macedonia and had come within 12 miles of the capital Skopje.

The NLA threatened to bomb strategic targets, such as the Skopje International Airport and the oil refinery, Okta AD.

[42] Approximately 400 young Albanian men from Macedonia,[43] including figures like Ali Ahmeti, Gëzim Ostreni, and Xhezair Shaqiri, had fought within KLA's ranks.

Nonetheless, the NLA had a broader network of supporters involved in tasks such as reconnaissance, patrolling, communications, and logistics.

[49] However, a distinction was noted between the fully armed front-line forces, numbering 2,800–3,500, and the remaining 2,000 personnel serving as rear-echelon support and logistics staff.

[44] As the war progressed the rebels managed to acquire heavy weapons including T-55 tanks and armoured personnel carriers captured from Macedonian government forces.

According to Human Rights Watch: "Ethnic Albanian rebels in Macedonia tortured, sexually abused road workers after abducting them from the Skopje–Tetovo highway.

[60][61] The Macedonian government accused the NLA of bombing a 13th-century Orthodox monastery Sveti Atanasij in the village of Lešok on 21 August 2001.

[64] NATO military experts said that "the fact that the battery was lying within an area spattered by rubble and wreckage seemed to suggest that it was detonated using a relatively sophisticated timer device;".

[79] Ali Ahmeti later formed the Democratic Union for Integration (which also included former NLA members), which has been the biggest Albanian political party in North Macedonia.

[70][80] In April 2010, a weapon cache believed to be intended for group actions was discovered near the border with Serbia; it included uniforms with UÇK marks.

[86] On 21 April 2015, a group of 40 armed men with UÇK patches attacked a border police station at Gošince.

[95][96] According to Nikola Gruevski the armed group did not have the support of members of the Albanian minority contrary to the 2001 conflict.