A rebel ethnic group in northern Myanmar said they shot down a government military helicopter in heavy fighting for a strategic position on Monday.

The Army’s demand for Kachin Independence came as protests against Myanmar’s military government continued in Kachin State and elsewhere in the country. It would be the first plane shot down in recent hostilities between the government and ethnic guerrilla armies.

The Kachins are one of many ethnic minorities who have allied themselves with the nationwide protest movement against the army’s eviction in February by the elected government of Aung San Suu Kyi, who was arrested and remains in detention. The country’s ethnic minorities have fought for decades against the central government for greater autonomy.

A government offensive is underway against the Kachins and Karen, another ethnic minority in eastern Myanmar who maintains its own armed force and has also been the target of airstrikes. The fighting in Kachin and Karen states has displaced more than 45,000 villagers.

Colonel Naw Bu, spokesman for the Kachin Independence Army, said his group’s forces shot down the plane after the junta used helicopters and jet fighters in an attack on the township of Momauk, where the Kachins seized a government base on March 25.