Residents of San Jose, Costa Rica, took to the streets today just after lunch as an earthquake registering 6.1 on the Richter scale shook the capital city. Windows broke, walls cracked and landslides were triggered in the countryside, but so far no casualties have been reported.

The epicenter of the quake at 1:21 P.M. local time was just 20 miles (35 kilometers) northwest of the capital, the U.S. Geological Survey reports, and originated 8.6 miles (14 kilometers) beneath Earth's surface. Aftershocks have been reported throughout the afternoon.

Costa Rica is located in the middle of Central America and makes up part of the "Ring of Fire" circling the Pacific Ocean; it is home to several active volcanoes, including Poas, which erupted just last year and Arenal, which erupted in 2007. A similar strength quake in 1910 killed at least 700 people in the city of Cartago; more recently a temblor measuring 6.4 shook the capital in November 2004, killing eight.

For more on such earthquakes and the surprising places they occur, see's Guide to Earthquakes.

Update (1/9/08): One of the commenters to this blog is in Costa Rica and posted his firsthand account here.