It said 15 people were swept away and six were later rescued. The National Disaster Mitigation Agency said rivers on the slopes of Mount Arjuno overflowed their banks on Thursday and their muddy waters inundated five hamlets in Kota Batu, a city in East Java province. KOTA BATU, Indonesia (AP) - Flash floods from torrential rains on Indonesia’s main island of Java killed at least six people and three others were missing, officials said Friday.