Lava flows from the Kilauea volcano on Hawaii’s Big Island wiped out hundreds more homes and then quickly filled a nearby coastal bay, officials said on Tuesday, pointing to a volatile new phase in the eruption of one of the world’s most active volcanoes.

Janet Snyder, a spokeswoman for Hawaii County, said that the authorities were still seeking to get a definitive number of homes destroyed in recent days. “But it’s safe to say that hundreds were lost in Kapoho Beach Lots and Vacationland overnight,” Ms. Snyder added, referring to largely rural communities on the island’s far eastern edge that had been largely evacuated ahead of the lava’s powerful new advance.

Mayor Harry Kim’s second home was among the residences destroyed overnight, Ms. Snyder said.

Kilauea has been erupting with greater intensity since early May in parts of the Big Island, forcing thousands to evacuate while dealing a severe blow to the island's tourism industry. Until the overnight destruction, a total of 117 homes had been razed in recent weeks by the eruption, which has also spewed ash thousands of feet into the air.