Warning: Some of the details may be distressing to readers

A three-year-old boy is dead after he apparently fell in a “grease trap” outside a Tim Hortons in the U.S.

The small hole was reportedly used as disposal for excess grease from the kitchen at the Rochester, N.Y., Tim Hortons.

According to police, the young boy went missing just before 11 a.m. He was found a few minutes later by a witness who reportedly pulled him from the hole, which was about one metre in diameter. Attempts to revive him failed and the boy was later pronounced dead at the hospital.

“What occurred today was a tragedy and on behalf of the Tim Hortons family, we offer our deepest condolences to the family and friends of the young boy who passed away,” wrote a Tim Hortons spokesperson in an email. “Tim Hortons is fully cooperating with authorities. As there is an ongoing police investigation, we have no further comment at this time.”

The boy reportedly fell through a plastic cover concealing the hole. Restaurant grease traps are designed to keep used oil and grease out of sewer systems, but are not always properly sealed. In Alabama, stricter legislation was passed requiring more secure covers after the 2017 death of a three-year-old girl in a grease trap. In Oklahoma, a five-year-old girl was rescued from a similar trap last year.

Police have not released the boy’s name or any details about his family, but said no charges are being filed at this time. According to CNN, police expressed concern about the grease hole, which they said had no fencing around it and was level with the ground.

Footage captured by CNN Monday showed distraught Tim Hortons employees pacing in the Rochester parking lot behind yellow police tape.

In the footage, a woman sitting on the curb next to police can be heard repeating “He has to be OK, he has to be OK.”

“We’re asked all the time ‘What’s the worst thing that you encounter as a police officer?’ and this is number one,” an emotional Frank Camp, an investigator with the Rochester Police Department, said during a CNN interview. “We have a horrifying episode that happened here today,” he added. “Our hearts are really going out to the family for this. It’s just a horrible, unimaginable, unspeakable tragedy.”

The grease trap was expected to be sealed Monday.

With files from The Associated Press