Breathing harder than usual, a white horse named Max stumbled on the street. The red carriage he'd been pulling behind him came to a halt. Then Max fell. He struggled to get back up — when he did, he managed to take a couple steps forward. But then he fell again, his body flattening against the asphalt.

Carriage horse in New York City collapsesNYCLASS

Max is one of many horses who pull carriages around Central Park in New York City, and it was the beginning of last Tuesday's morning shift, which began every day around 10 a.m. But based on Max's condition, it was obvious that he shouldn't be working, and that something was seriously wrong.

A passerby snapped a few photos of the fallen horse, which eventually found their way to NYCLASS, an advocacy group that campaigns against the use of carriage horses in New York City.

When the photos went viral, the driver of the carriage, Chris Emanus, was quick to give his side of the story.

Carriage horse in New York City collapsesNYCLASS

"He tripped," Emanus told Daily News New York. "His foot got stuck on a little crack on the pavement. He went down. That happens all the time with horses. With new shoes, sometimes they're not comfortable."

However, Jill Carnegie, a spokesperson for NYCLASS, isn't buying Emanus' explanation.

"What we do know based on the witness account was that this horse was breathing heavily, and then collapsed to his side, took a few moments to right himself, took a few steps, then collapsed a second time," Carnegie told The Dodo "So that does not sound like a horse who tripped."

Carriage horse in New York City collapsesNYCLASS

Unfortunately, these kinds of incidents are common in New York City. For instance, last September, people watched as a driver screamed at a 14-year-old draft horse named Norman who collapsed from exhaustion in the middle of New York City traffic.

Curiously, Norman's driver also claimed that Norman had tripped and fallen.

While Max's and Norman's falls were documented, Carnegie believes that other incidents slip under the radar.

"So many go unreported," Carnegie said. "It is speculated that these incidents happen all the time. In fact, the driver even said in one of his news interviews that horses trip and collapse all the time. And that it's 'normal.' Yet anyone who knows horses know that it's not normal for a quadruped animal to frequently trip or collapse."

Carriage horse in New York City collapsesNYCLASS

Besides the fact that these horses collapse, Carnegie believes that the carriage industry is generally very hard on the animals.

"These horses are standing on ... asphalt, for at least nine hours a day, inches from traffic, and they are wearing a bridle and aggressive metal bits in their mouths for a minimum of nine hours straight," Carnegie said. "That in itself would be considered by most caretakers abuse."

"That's not even factoring in subjecting them to traffic, loud city traffic, the fumes from cars," she added. "Many of them [the horses] hang their heads low and just breathe in the car fumes. Many of them are eating feed that's contaminated with pigeon feces, and many of them are eating feed off the asphalt itself, which is on the two-way traffic street, Central Park South."

At the moment, it's not clear what happened to Max to make him collapse, but NYCLASS is asking for a formal investigation to occur.

Carriage horse in New York City collapsesNYCLASS

"Horses don't just collapse," John Collins, a NYCLASS spokesperson, said in a statement. "Something happened — and the city should get to the bottom of it and make sure it never happens again. They should conduct an immediate investigation into the health and whereabouts of this horse, including allowing an independent vet to examine the animal."

The Humane Society of the United States (HSUS) is calling for the end of the horse carriage industry in New York City.

"In the wake of this reported incident of Max's alleged collapse while pulling a carriage in New York City, and the dozens of other documented calamities over the years involving carriage horses on crowded streets, The HSUS reiterates our support to finally bring an end to the abuses within the carriage horse industry," Marty Irby, senior advisor at HSUS, told The Dodo.

"Our modern day society should not tolerate animal abuse on any level, much less, for entertainment," Irby said. "This isn't ancient Rome — it's 2017. The City of New York should continue to lead efforts that would end the harm and use of carriage horses when more humane and modern options exist."

Carriage horse in New York City collapsesNYCLASS

If you see a carriage horse in distress in New York City, Carnegie says, the best thing to do is document the situation with photographs and video and send everything to NYCLASS.

Carnegie also stresses the importance of calling 911.

"That 911 call then is tracked and recorded, and, if the police think it's appropriate, they can file a report," Carnegie said. "That's why it's so crucial to call someone when this happens — otherwise, no one knows. And the industry is certainly not going to compromise itself by revealing what's going on."

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