More than 300 earthquakes have erupted at Washington's Mount Rainier this week, the largest earthquake swarm at the volcano since 2009.

Officials are tracking the largest swarm of earthquakes in more than 15 years on Washington's Mount Rainier but say there is no indication that the cluster of quakes is cause for concern. The U.S. Geological Survey Cascades Volcano Observatory said the swarm began early Tuesday at the 14,

Mount Rainier is an active stratovolcano 45 miles southeast of Tacoma and 60 miles south-southeast of Seattle. Its last eruption was "a light dusting of ash" in 1894, the USGS said in a report. Large eruptions haven't occurred for more than 1,000 years.