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

The icy pond in Gaithersburg where a 10-year-old boy died this week was supposed to have been bordered by a safety fence, Gaithersburg city officials said Thursday.

But for reasons that were unclear, about half of the fence had been removed, and Gaithersburg officials issued a Notice of Violation this week to a company that is developing a large piece of land adjacent to the boy’s neighborhood.

It is not clear whether a full fence would have prevented the drowning. The fence was required to be at least 42 inches tall, a height that could possibly be climbed over. But the revelation has added a new layer to the tragedy that has torn through a family and a community.

“We remain deeply saddened by the tragic loss of a young boy’s life and our hearts go out to the youngster’s family and friends,” said Charles Maier, a spokesman for VII Crown Farm Owner LLC, the property owner.

About 4 p.m. Monday, D’Angelo “DJ” McMullen and two of his young friends walked onto the retention pond to slide across it in their shoes. The ice broke. Two of the boys, including D’Angelo’s brother, got out, but D’Angelo went under the water. He was pulled out by divers but died a short time later at a hospital.

D'Angelo McMullen (Family photo)

The body of water serves as a sediment pond for a large Crown construction project — a mix of stores, restaurants, apartments and houses. As part of its regulatory process, Gaithersburg officials required safety fencing for the pond. The fence “must be at least 42 inches high, have posts spaced no farther apart than 8 feet, have mesh openings no greater than 2 inches in width and 4 inches in height, with a minimum of 14-gauge wire,” the officials said, citing documents for the project. It is unclear how long the fencing was supposed to have been in place.

When Gaithersburg inspectors looked at the site Tuesday, they determined that the removed portion of the fence should have still been in place and issued the notice.

Maier, the spokesman for the property owner, declined to discuss specifics. “We are in contact with city officials about it and will continue to investigate the matter until we have all possible answers," he said.

Jennifer Jenkins contributed to this report.

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