A report by KREM News of Spokane, WA says they were running loose on Highway 155 near Nespelem but were corralled by tribal members.
The fires were started by lightning and are burning on the Colville Reservation.
The overview at InciWeb for the Chuweah Creek fire shows 22,900 acres burned, 20% containment and expected movement to the north and east.
Western Horse Watchers Association 