A loud rumble and giant billows of dust interrupted an otherwise serene day in Central Park on Thursday as hundreds of cream-colored carvings of dragons, Buddhas and horses awaited their public execution.

Onlookers waved paper fans reading “Protect their home.” They cheered as sculptures and jewelry made from elephant tusks were carried on a conveyor belt and dropped in a pulverizer.

Brian Hackett, an animal-welfare activist from New Jersey, patiently awaited his turn to choose a carving from a table to be destroyed. For him, the mood was solemn.

“Every piece, no matter how polished, represents a beautiful animal that was slaughtered,” Mr. Hackett said.

The carvings were confiscated in recent ivory busts in New York. They once belonged on the faces of a least 100 slaughtered elephants. Nearly two tons of ivory worth about $8 million was destroyed at the “Ivory Crush” event, which was timed to precede World Elephant Day on Aug. 12.

In 2014, New York was among the first states to prohibit the sale, purchase, trade or distribution of items made from elephant and mammoth ivory and rhinoceros horns.

The law helped “spur the world into action for elephants,” said John Calvelli, executive vice president of public affairs at the Wildlife Conservation Society, in a statement.

“By crushing a ton of ivory in the middle of the world’s most famous public park, New Yorkers are sending a message to poachers, traffickers and dealers who try to set up shop right here on our streets,” Mr. Calvelli said in the statement. “We won’t stand for the slaughter of elephants. Nobody needs an ivory brooch that badly.”

About 96 elephants are killed each day in Africa because of ivory poaching, according to the society and the New York State Department of Environmental Conservation. All of the ivory destroyed on Thursday came from the undercover work of 300 officers during the past three years. While some of the ivory was found in Buffalo and Albany, 95 percent was found in New York City, said Basil Seggos, the commissioner of the environmental conservation agency.

Over half of the ivory was confiscated from Metropolitan Fine Arts and Antiques in Midtown Manhattan, which state officials raided in December 2015. From intricate carvings to a $200,000 pair of tusks, 126 ivory items were at the store.

On July 26, the brothers Irving Morano, 47, and Samuel Morano, 49, pleaded guilty to illegally selling and offering for sale more than $4.5 million worth of ivory. As part of their sentence, they forfeited all the seized ivory and an additional 1,657 ivory carvings, all of which were crushed on Thursday.

Mary Banerian, 67, who watched the destruction in Central Park, went to Western Africa in the 1980s, when there were fewer regulations, and remembered seeing about 10 elephant tusks for sale there.

She said seeing the ivory be rendered valueless on Thursday was “long overdue” and she hoped the destruction would hurt poachers and dealers.

“I feel terrible that those elephants had to die to make those items,” she said.

The event was the second Ivory Crush in New York, after one in Times Square in 2015. The first in the nation was in Denver in 2013.

Rachel Karr, 48, the owner of Hyde Park Antiques on the Lower East Side, who specializes in 18th-century antiques, said the ivory-crushing events upset her and other antique collectors because some of the ivory found in bona fide antiques could be 300 to 400 years old and could have religious and historic value. For example, in teapots from the 18th century, the handles were carved from ivory to protect hands from burns, because ivory does not conduct heat

“Even with my love of nature, I simply cannot understand what good it does to destroy things that were worked on 300, 400 years ago before conservation was part of daily language,” Ms. Karr said.

“Face it, we’re the original recyclers, antique dealers,” she said. “We have no interest in using new ivory at all. We are willing to say we aren’t willing to use it to repair old ivory.”

Sam Wasser, a professor at the University of Washington who has performed forensic analysis on seized ivory for the last 13 years and analyzed the ivory that was crushed, said it was unlikely the destroyed carvings were more than 100 years old. The results are pending.

Iris Ho, who is the wildlife campaigns manager at Humane Society International, said the existing law does enough to protect antiques. The law provides exceptions for antiques that are determined to be at least 100 years old with only a small amount of ivory.

“Even if it’s old,” Ms. Ho said, “as long as you have an ivory item, you are perpetuating the myth that ivory has value and is collectible.”