BANDUNG, Indonesia, March 19 (UPI) -- Seventeen of 18 volcanoes in Indonesia are on alert status and emitting toxic gas, a federal monitoring agency said.
The mountains are safe to visit as long as tourists stay at least a half-mile away from the gas-producing craters, Indonesia's Volcanology and Geology Hazard Mitigation Center said.
The alert status is the second level of a three-level system of warning. The Ibu volcano in West Halmahera is the only one of the 18 volcanoes at the lower No. 3 standby level, Antara news reported.
Mount Talang in Sumatra and Mount Karangetang in Sulawesi are the most recent volcanos to have their status raised to alert.
Other Indonesian volcanoes on alert include Krakatoa, Bromo, Kaba, Anak, Slamet and Lokon.
In 1883, Krakatoa erupted in an explosion equivalent to 200 megatons of TNT -- about 13,000 times the force of the U.S. bomb that devastated Hiroshima, Japan, during World War II.