YOGYAKARTA, Indonesia (AP) — Indonesia’s most active volcano has erupted with a river of lava and searing gas clouds flowing down its slopes. A monitoring official says the lava flow is Mount Merapi’s longest since the mountain’s danger level was raised in November. Authorities at that time evacuated nearly 2,000 people living on the mountain but most have since returned. A warning for people to keep at least 3 miles from the crater is still in effect. Merapi is on densely populated Java island near the ancient city of Yogyakarta. It is the most active of dozens of Indonesian volcanoes.