<p>JAKARTA A 6.1-magnitude earthquake struck off Indonesia's main island of Java on Saturday, the US Geological Survey reported, but local officials said there was no risk of a tsunami.</p><p>The quake struck at 12:14 pm (0514 GMT), 39 kilometers (24 miles) south-southeast of the coastal town of Adipala in Central Java province at a depth of 83 kilometers, the USGS said.</p><p>"There's no potential for a tsunami and we haven't received any reports of damage or casualties so far," meteorology, climatology and geophysics agency technical chief Suharjono, who goes by one name, told AFP.</p><p>Indonesia sits on the Pacific "Ring of Fire", where tectonic plates collide, causing frequent seismic and volcanic activity.</p><p><a href="http://www.gmanetwork.com/news/story/345524/news/world/6-1-magnitude-quake-strikes-off-indonesia-s-java-usgs">Keep reading...</a></p>