Tokyo Gov. Shintaro Ishihara on Sunday asked the Self-Defense Forces to dispatch a disaster-relief team to Miyake Island to help remove volcanic ash and otherwise assist residents of the island in the wake of a volcanic eruption.
This is the second dispatch of an SDF relief team to the island since June 26, after volcanic activities began earlier that month.
The latest force consists of around 300 members from the Ground Self-Defense Force's first division, officials said.
The relief team, which left for Miyake Island Sunday evening, will clean up the ash that is covering the island and pile up sandbags to help prevent mudslides, they said.
Miyake Island's Mount Oyama erupted Friday evening, sending smoke some 8,000 meters into the air, the highest altitude of any of the volcano's recent eruptions.
Meanwhile, a fairly strong quake measuring 5.0 on the open-ended seismic-magnitude scale jolted the Izu islands chain south of Tokyo on Sunday afternoon, the Meteorological Agency said.
There were no immediate reports of casualties or damage from the 4:24 p.m. quake.
The quake registered 4 on the Japanese intensity scale of 7 in Shikinejima, Kozushima and Miyake Island and its focus was in waters just off Miyake Island, according to the agency.
Two moderate earthquakes hit the same chain of islands earlier in the day. The first quake, with a magnitude of 3.9, occurred at 5:35 a.m., followed by a magnitude 4.3 quake 11 minutes later.
The first quake registered 3 on the Japanese intensity scale on Shikinejima, while the second quake had an intensity of 4 on Niijima and Kozushima islands.
The focus of both quakes was about 10 km below sea level near the isles of Niijima and Kozushima, the agency said.
Parts of the Izu chain, some 100 to 360 km south of Tokyo, have been hit recently by a series of quakes due to magma activity.