A massive earthquake measuring 7.7 on the Richter scale hit Solomon Islands on Thursday. The Pacific Tsunami Warning Center had issued several alerts, including one for Hawaii, before withdrawing them. No casualties have been reported yet.

The United States Geological Survey had revised the quake’s magnitude down from 8.0 and pegged its depth at 40 km. Its epicentre was 70 km from the island city of Kirakira.

Solomon Islands National Disaster Management Office Director Loti Yates told Reuters that several buildings had collapsed and a helicopter-borne team had been dispatched to assess the situation in Malaita, an island close to the epicentre where a quarter of the total population lives.

The Pacific Tsunami Warning Centre had initially issued an alert about possible “widespread, hazardous” tsunami waves, but it downgraded the threat levels three hours later. Officials said affected citizens had been evacuated and relocated to higher sites, and some residents of Honaira – the capital of the South Pacific nation – were returning to assess the damage caused to their homes.

The islands are located in the Pacific Ring of Fire, where the world’s most active faultlines are located. There are more than 400 underwater volcanoes located along the horseshoe-shaped ring, which extends from New Zealand through Japan to the tip of South America, CNN reported.

In 2007, the region was struck by a deadly tsunami, which was triggered by an 8.1-magnitude earthquake. Around 50 people had died, and dozens were left missing.