LUANDA, Angola (AP) _ UNITA rebels reportedly shot down an army helicopter in southern Angola, killing 22 soldiers, but the government said today the four-day-old truce was not endangered.

The MV-17 copter was downed Friday in southeastern Cuando-Cubango province as it transported sick and wounded soldiers from the garrison of Cuito Cuanavale to the provincial capital Menongue, the official Jornal de Angola reported.

The government and UNITA signed a peace accord Sunday in Lusaka, Zambia, to end their 19-year civil war that has killed 500,000 Angolans since independence from Portugal in 1975. A truce was declared Tuesday.

UNITA's Radio Vorgan did not report the helicopter shooting but claimed government troops Friday had captured the town of Cambulo in the diamond-rich northeastern Lunda provinces.

There was no independent confirmation of either report. Fighting generally seems to be easing across the vast southern African nation.

The Jornal de Angola said violations should not upset the peace deal, brokered painstakingly for a year by U.N. mediator Alioune Blondin Beye.

''Despite initial skepticism, the idea is gaining ground that peace is here to stay,'' said an editorial in today's editions. ''Small flare-ups of military tension do not endanger the essence of this peace.''

Beye met with government leaders Friday and expects to welcome UNITA officials in Luanda next week for the first session of a joint commission to monitor the accord, which is to lead gradually to power sharing between government and UNITA, the National Union for the Total Independence of Angola.

The United Nations has pledged 7,000 peacekeepers to anchor the Lusaka accord, but will deploy them only once the truce holds.