Two days after a colossal volcanic eruption spawned a tsunami that struck the island nation of Tonga, severed communication lines left Tongans around the world waiting anxiously for news of their loved ones, while aid agencies and the country’s Pacific neighbors struggled to assess the scale of the damage.

On Saturday night, an undersea volcano about 40 miles north of Tonga’s main island belched ash, gas and steam more than 12 miles into the air, creating a cloud of sulfur dioxide over the region, sending particles drifting across the island and disabling a crucial submarine internet cable. It was believed to be the largest volcanic eruption in three decades, with the shock wave traveling thousands of miles.

Hours later, Tonga, a country of around 100,000 people, was pummeled by a tsunami. Waves of up to 4 feet hit Nuku’alofa, the Tongan capital. Footage shared in the final moments before the internet connection was cut showed people running inland, searching desperately for higher ground in a very flat country.