Blank map of Costa Rica for geo-location purpo...
Blank map of Costa Rica for geo-location purpose. Note : The Isla del Coco, out of the map, is not shown. Scale : 1:14,816,000 (accuracy : about 3,7 km) (Photo credit: Wikipedia)

Three dead, 20 injured as major earthquake damages Costa Rica coast

Updated at 3:35 p.m. ET: Three people died, two them from heart attacks, when a major earthquake hit northwestern Costa Rica on Wednesday, authorities said. At least 20 people were injured and two others were missing, but the Red Cross said those numbers could rise as damage assessment teams reached more areas.

Robert Bazell, Amy Jean Goodwin, Tom Lea, Miranda Leitsinger and Edgar Zuniga Jr. of NBC News contributed to this report. Follow M. Alex Johnson on Twitter and Facebook.

The quake — initially rated at magnitude 7.9 but then revised by the the U.S. Geological Survey to 7.6 — struck at 10:42 a.m. ET at a depth of about 25 miles about 7 miles southeast of Nicoya. The town of 15,000 people is near the Pacific coast, about 90 miles from the capital, San Jose.