Nov 28 (Reuters) - An eruption began in the summit caldera of Hawaii's Mauna Loa, the world's largest active volcano, on Sunday night, the U.S. Geological Service's (USGS) volcanic activity service said."At this time, lava flows are contained within the summit area and are not threatening downslope communities," the notification said.However, the notification warned, based on previous events, that the early eruption stages of this volcano can be very dynamic and the location and advance of lava flows can change rapidly.Mauna Loa, which takes up more than half of the Big Island in Hawaii, and rises 13,679 feet (4,169 meters) above the Pacific Ocean, last erupted in March and April of 1984, sending a flow of lava within 5 miles (8.05 km) of the city of Hilo.Volcano GraphicsTonga Eruption: The perfect stormHow big was the Tonga eruption?"