Three young brothers, ages 6, 8, and 9, died in Texas after falling through an icy pond during a massive winter storm, authorities said.

The boys fell into the private pond Monday near Bonham, a rural town near the Oklahoma border, and were pulled from the water by first responders and a neighbor, though all three later died.

Their mother, who tried to save them, said the freezing water made it impossible to rescue them on her own.

The boys attended elementary school in the Bonham district, which canceled classes due to the severe weather, ABC News has reported.

The tragedy adds to the more than 40 deaths reported across U.S. states affected by the extreme cold.