A city, other incorporated entity, and other fire protection groups may organize a mutual-aid program by adopting an ordinance or resolution authorizing and permitting their fire department, fire company, emergency relief squad, fire police squad, or fire patrol to go to the aid of another city, incorporated entity, or fire protection group, or territory outside of it. While extending aid under this section and Alaska Stat. § 18.70.160 the fire department, company, squad, or patrol has the same privileges and immunities it possesses when it performs the same functions in its own area. The ordinance or resolution may authorize the heads of the fire department to extend aid, subject to conditions and restrictions prescribed in the ordinance or resolution.