Investigators say embers from a backyard fire spread rapidly, fueling blazes that prompted evacuations and an emergency burn ban.

At least four wildfires broke out on New York's Long Island over the weekend, threatening the Hamptons as people on social media shared videos of the flames and smoke billowing into the sky above.

All four Long Island brush fires that sent soaring plumes of smoke into the air had been contained by Sunday afternoon, authorities said.

The last of four blazes that began in Suffolk County on Saturday has been put out, but Long Island and the Hudson Valley still faced a high fire risk on Sunday, officials said.