It happened around 7:45 p.m. on Friday on Willoughby Avenue in the Bushwick section.
The wall was about five feet high and 25 feet across and fell on top of 11-year-old William Arroyo and 10-year-old Nathiaz Figueroa.
They boys apparently went by the wall to get a ball.
The children were rushed to the hospital with serious head injuries. Arroyo is said to be in critical condition.
The father of one of the boys says that construction work is being done next to the wall and that may have compromised the structure.
The wall separates the home from a vacant lot adjacent to the property.
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