(CNN)The US Geological Survey Hawaiian Volcano Observatory has raised the volcano alert from advisory to watch for the Kīlauea volcano after an increase in earthquake activity under the south part of the Kīlauea summit caldera within Hawaiʻi Volcanoes National Park, according to release from the USGS.
Kilauea volcano alert raised as a swarm of small earthquakes hits the region
While the Kīlauea volcano is not erupting, "the onset of the earthquake swarm was coincident with a change in the style of ground deformation at tiltmeters in the Kīlauea summit region, potentially indicating the shallow movement of magma beneath the south part of Kīlauea caldera," the release states.
Over 140 earthquakes were recorded by 4:30 a.m. (10:30 a.m. ET), with the largest being a magnitude 3.3. Most of the earthquakes were less than magnitude 1, but small earthquakes are continuing at the rate of at least 10 earthquakes per hour, the release adds.
The aviation color code has also increased from yellow to orange, though USGS says no smoke cloud has formed.
In December, the Hawaii County Civil Defense Agency asked residents to stay indoors after the Kilauea volcano erupted following a series of earthquakes.