Tokyo, Rajab 1, 1436, Apr 20, 2015, SPA -- A magnitude-6.8 quake struck the small southern Japanese island of Yonaguni early Monday, prompting authorities to issue tsunami warnings for the region, according to dpa. The quake occurred at 10:43 am (0143 GMT) with its epicentre off Yonaguni, located just over 100 kilometres east of Taiwan, the Japan Meteorological Agency said. No immediate casualties or damage were reported. --SPA 11:14 LOCAL TIME 08:14 GMT www.spa.gov.sa/w