Over the past few weeks, an animal welfare crisis in the heart of Skid Row has exploded into a full-blown catastrophe after four pugs died and one French Bulldog suffered a fentanyl overdose and was left clinging to life.

In response, a coalition of Hollywood big shots that includes famed Hollywood litigator Marty Singer, “Sons of Anarchy” star Ron Perlman and Oscar winner Kim Basinger, has banded together to hold Mayor Karen Bass and a derelict LAPD accountable.

Members of the group are even throwing shade at City Councilwoman Nithya Raman, who will face off against Bass in a tight election this fall.

The ongoing crisis peaked in late May, when animal rescuers attempted to save a litter of pug puppies being illegally bred by a homeless man living within the 50-block area of downtown Los Angeles, after their mother was struck and killed by a vehicle. That left a trio of two-week-old puppies requiring bottle feeding every two hours to survive. The homeless breeder allegedly refused to surrender them.

Members of the coalition say the situation was reported to the LAPD’s Lieutenant Andrew Mathes, who said he would send in undercover officers, as well as the mayor’s office.

Despite repeated requests for help, no action was taken for two weeks. They say that inaction led to devastating consequences. Two puppies died from starvation, we’re told. The final surviving puppy was passed among several Skid Row inhabitants before rescuers were finally able to secure her. The puppy, later named North Star, was rushed to an emergency veterinarian. After fighting for her life for 48 hours, she passed away.

In a separate Skid Row incident on June 16, a rescuer received a report about a French bulldog that had been abandoned on the street outside an encampment for several days, repeatedly losing consciousness.

Compton Paw Control, with actor Joey Tuccio, transported the dog to an emergency veterinary hospital where toxicology testing revealed exposure to cocaine, amphetamines, methamphetamine, MDMA and fentanyl. The male dog, later named Valor, was administered Naloxone and has begun to bounce back.

“Animals are being tortured on Skid Row, and a civilized society cannot allow these horrors to occur. Animal abuse is illegal and we must not tolerate it,” Singer tells Page Six Hollywood. “These brutal people need to be prosecuted just like other criminals.”

The group of outraged industryites, which also include Jennifer Coolidge and Alicia Silverstone, have enlisted the legendary Hollywood lawyer best known for sending scary cease-and-desist letters on behalf of a who’s-who list of clients that has included Arnold Schwarzenegger, Michael Jackson, Scarlett Johansson and Britney Spears over the decades.

Singer, who was brought into the fray by his daughter, Los Angeles-based stylist and board member of I Stand With My Pack Rescue, Nola Singer, is considering filing additional lawsuits on behalf of the animals.

In December, writer and animal advocate Rebecca Corry filed a lawsuit against Bass and the City of Los Angeles in LA Superior Court over the ongoing abuse and negligence.

Corry also slams City Councilwoman Raman for pledging to protect animals and then walking out of a City Hall session as soon as the topic arose. (Raman did not comment.) The nonprofit law firm, Advancing Law for Animals, has also already filed a federal complaint with the FBI and Attorney General demanding the feds step in given the inertia of the city.

With the problem continuing to persist, Ron Perlman and his wife Allison Dunbar are sounding the alarm and are willing to call out Mayor Bass.

“This isn’t complicated. If you’re the mayor of Los Angeles and animals are dying on your streets while there are systems, funding and agencies supposedly in place to protect them, then you are not doing your job,” Perlman says. “Meanwhile independent rescuers are fighting every day to keep these animals alive. At this point, the question is no longer awareness. It is responsibility.”

The city and state already have robust laws in place that are being ignored, according to the group — as illegal breeding and the sale of puppies for money and drugs continue openly on Skid Row with little to no enforcement, the group says.  (The LAPD did not respond to a request for comment.)

Meanwhile, the same Skid Row breeder apparently has five additional pugs still in his possession. The animal advocates are particularly concerned given that pugs are a brachycephalic breed that are vulnerable to heat and susceptible to breathing difficulties. With summer temperatures rising, the remaining dogs are at serious risk while living in a tent on Skid Row.

The group is urgently asking city officials — including Mayor Bass, Animal Services and law enforcement — to intervene before more animals suffer and die.

Tuccio, who played a bartender on the CBS soap “Guiding Light,” has spent years documenting the abuse. “Karen is letting criminals get away with actual murder,” he says of the mayor’s inaction. (Bass did not respond to a request for comment.)

“Yellowstone” actress Dunbar calls the predicament “unacceptable and heartbreaking.” She adds: “Animals are completely dependent on us, and when they are let to starve, suffer and die while resources and systems are supposedly in place to protect them, something is deeply broken in Los Angeles.”

Silverstone shared on her Instagram a screenshot of a petition highlighting the issue with a picture of a dog that appears to have had its eyes glued shut or gouged out. “These dogs on Skid Row are suffering beyond the unthinkable, and they need our help. We can’t look away. Please sign if you can. Every voice matters.” The petition currently has 21,948 signatures.

Basinger has also been sharing posts on Instagram to help raise awareness.

Former candidate Rick Caruso has called what’s happening “a diabolical mess” that is “so disgusting it’s difficult to even talk about.”