The retention pond where 10-year-old DeAngelo McMullen died Monday when he tried to ice skate with friends. (Dan Morse/The Washington Post)

The three boys were “just being boys,” a Montgomery County fire department official said, going out onto the ice on a sediment pond in their neighborhood.

They called it skating, a friend said, sliding across the surface of the pond in Gaithersburg in their shoes, without blades attached.

But it has been warm in the Washington area since the ice formed on the pond in the Crown Farm neighborhood, and it apparently was not particularly thick or firm Monday afternoon when the boys broke through the surface and fell into the muddy water. One of them died. He was 10 years old, said Assistant Fire Chief Scott Graham.

Montgomery County police identified the boy Tuesday as D’Angelo McMullen.

Firefighters were called about 4:15 p.m. Monday to the pond on Diamondback Drive near Reprise Drive.

D'Angelo McMullen (Family photo)

Arriving rescuers found that one of the three children, all described as between 9 and 11 years old, had reached a spot of relative safety. A second boy had broken through the ice, but the water was relatively shallow where he went in, Graham said.

The third boy was not to be seen. Firefighters went into the pond to search for him.

The firefighters “were just grabbing at anything,” said Nemo Young, who lives in the area and was picking up her nephew from a bus stop.

Young, who said she had previously seen the boys playing, watched the rescue effort from the shore. “They just kept grabbing” until they got the last boy, she said.

The boy was taken to a hospital, where he died Monday night, Graham said. He said the boy may have been in water five or six feet deep for as long as 30 minutes.

The friend who said he had learned of Monday’s after-school plans to “skate” on the pond said they had done it previously without incident.

“They did it, but nothing happened before,” said the child, Alex Bermudez, 11.

He said the boy who died and his 11-year-old brother, who he said had also gone onto the ice, had moved to the area about a year ago. Sometimes they would play football on a grassy patch or go indoors to play video games.

“We know these little guys,” said Israel Bermudez, Alex’s father, who has lived in the area for a dozen years. “It’s so sad,” he said. “They are beautiful, great kids.”

The severe cold snap last week turned the surfaces of many bodies of water in the Washington region into ice. Sheets of ice formed on the Potomac River.

But in the past few days, temperatures have risen sharply, well above the freezing mark and as high as the 50s.

“There is no ice in this county that can withstand human weight,” Graham said. “It may look like fun, but please don’t,” he said, referring to the temptation to venture onto the ice.

Authorities said the two surviving children, who were brought to hospitals, appeared to be in relatively good condition. Television footage showed the two walking slowly to an ambulance, wrapped in robes or towels.

Rescue workers had their arms across the shoulders of each of them.

Peter Hermann contributed to this report.

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