Three powerful earthquakes struck near Vanuatu in the South Pacific in the space of just over one hour on Thursday. According to seismologists the first magnitude 7.8 quake sparked a region-wide tsunami alert and was quickly followed by two other strong earthquakes. The second quake was of 7.3 magnitude while the third one was 7.1 magnitude quake. Aftershocks also shook the region, with a 5.7 quake shaking Vanuatu and a 5.3 tremor striking near Samoa.