An earthquake measuring 6.9 magnitude on the Richter scale hit Tonga on Monday.The US Geological Survey (USGS) said that the earthquake was at a depth of 106 km. There have been no reports about human losses or material damage as a result of the earthquake so far.Tonga is an archipelago of 176 islands scattered in the South Pacific, of which only 52 are inhabited, located in northwest New Zealand and Australia.Source: Qatar News Agency