TANGERANG, Indonesia, Sept 7 (Reuters) - Seven Indonesian airports, including two serving Jakarta, remained closed on Monday morning because of volcanic ash from eruptions at Mount Anak Krakatau, the transport minister said.

Massive plumes of volcanic ash rose into the sky over Indonesia as Mount Anak Krakatau erupted again, with ash reaching up to 50,000 feet and forcing eight airports to suspend operations. The volcano,

Indonesia sits along the Pacific Ring of Fire, where as many as 120 volcanoes are active.