A 5-year-old girl was tragically killed in a freak Brooklyn accident when a three-foot-tall, six-foot-long ornamental granite fence toppled on her as her mother looked on, police said Friday.

Cops say little Alysson Pinto-Chaumana, who lived just a half-mile away, was standing in front of the six-pillar stone fence at 444 Harman Street in Bushwick when it crashed down on her at around 9 p.m. Thursday.

Surveillance footage obtained by The Post shows the child walk up to the heavy fence while inside the gated front area of the home moments before it suddenly falls on top of her.

Alysson is then immediately pulled out from under the fence by a woman as two other bystanders rush to help, the video shows.

The child suffered head trauma and was rushed her to Wyckoff Heights Medical Center, where she was pronounced dead.

Radhica Netchandra, 42, who owns the home with her husband, said that the little girl and her mother were at the home to visit the child’s uncle who lives on the third floor.

Netchandra, who had just gotten home from work at the time of the incident, said that she was inside eating when she “heard the screaming.”

“I heard them running downstairs. So I came out too because I thought there must be some kind of accident,” she said. “When I came out, the little girl was already in the ambulance.”

“I saw all the blood. I was shocked,” she said. “I heard people saying she was not going to make it because she hit her head.”

Netchandra said that last October she and her husband hired the contracting company to do a $35,000 renovation job on the outside of the home.

The contractors paved the front with concrete and put up the granite fence, she said, adding that they finished the work in January.

Records show that the city’s Department of Buildings issued a work permit for the front of the home in November to Manjinder Singh of Shah Group Enterprises.

The Buildings Department does not have records for the installation of the stone fence, and according to sources, residential fences under six feet can be installed without a DOB permit.

“Everything was completed and we paid the contractor,” she said. “We’ve been out there all summer. I love the outdoors. We sat out there. We barbecued out there. My husband and his friends sat out there and nothing happened.”

Netchandra said that she never knew that the fence “was loose.”

“I still can’t believe something like this could happen,” she said, adding, that she called the contractor in the aftermath and told him what happened. “He said he didn’t expect that and how can that happen.”

The victim’s uncle, Oscar Vega, 30, who lives at the home said he wants an “investigation into the work that was done.”

“It seems like it wasn’t done the right way,” said Vega, who was not home at the time of the incident.

The city’s Department of Buildings inspected the property after the incident and slapped the homeowner with a violation for failure to maintain the property.

The violation comes with potential fine of $6,250.

The DOB determined that the remaining section of the granite fence was loose, posing a potential hazard and the property owner was ordered to dismantle the fence once the agency’s investigation is complete.

A partial vacate order was issued by the DOB in the front yard and the sidewalk in front of the property was temporarily closed off.

According to the DOB, the agency did not receive any complaints about the fence prior to the incident.

Additional reporting by Ruth Weissmann and Yaron Steinbuch