TOKYO - There were no reports of injuries or damage from the eruption of Mount Asama, which is about 90 miles northwest of Tokyo.
The volcano erupted at 1:51 a.m. (11:51 p.m. EST) Monday, belching out a plume that rose about a mile high, according to Japan's Meteorological Agency. The plume was still roiling over the volcano's crater late Monday.
Chunks of rock from the explosion were found about 3,300 feet away from the volcano. Ash was detected over a wide area, including central Tokyo. In the town of Karuizawa, southeast of the volcano, the ash was thick enough to obscure road markings in some areas, town official Noboru Yanagishi said.
"Some people said they heard a strange noise in the morning when the eruption occurred," he said.