Thousands of people in the southeastern seaside town of Mallacoota were forced to seek refuge on the beach and even boats in the water early Tuesday as deadly blazes closed in around the popular holiday destination to create an apocalyptic-looking scene of huddled evacuees under dark-red skies.

As wildfires grip Australia in one of its worst fire seasons in memory, the threat is especially intense this week in southeastern states such as Victoria and New South Wales, where most of the country’s population lives. More than a hundred wildfires burning an area roughly the size of Belgium had killed at least three people in New South Wales; in Victoria, four are missing. At least 12 people have died during Australia’s fire season thus far.

A 63-year-old man and his 29-year-old son in New South Wales died while trying to save their home Tuesday, the Australian Broadcasting Corp. reported, and a volunteer firefighter died Monday. The New South Wales Rural Fire Service confirmed the three deaths Wednesday morning local time and expressed “grave concerns” for a missing fourth person.