SANTA CLARITA VALLEY – An illegal cockfighting bust on Monday in unincorporated Val Verde was the largest ever in the U.S., authorities said.

“Any type of animal blood sport activity is a serious crime and will not be tolerated in Los Angeles County,” Los Angeles County Sheriff’s Department Capt. Jeff Perry said during a news conference Tuesday, where officials played a video displaying what was found at the 80-acre property in the 29000 block of Jackson Street.

What was found was more than 7,000 roosters, including dead birds, a variety of weapons believed to be used in cockfighting contests – adding up to what was called the largest such seizure in the country’s history, Perry said.

Investigators also found recovered were hundreds of gaffs, or slashers, he said.

“They put them on the roosters’ claws so when they fight, they literally slash each other to death,” Perry said.

Syringes and steroids for the animals were also recovered, he said.

Perry, who commands the sheriff’s community partnership bureau, said the warrants served Monday in Val Verde were the culmination of a months-long investigation by detectives who specialize in “animal, blood sport type crimes.”

“It was very large and in a remote location in a canyon,” Perry said, who added that 100 sheriff’s department personnel secured the location and helped with animal care and control. .

Ten people were detained at the scene, Perry said. He described them as lower-level workers who took care of the animals. The property owner has been identified as the primary suspect but officials declined to name him.

“We anticipate to make several arrests in relation to this case,” Perry said.

The Humane Society received complaints earlier this year from area residents of suspected cockfighting going on in the Val Verde/Castaic area, said Eric Sakach, senior law enforcement specialist for the Humane Society. The complaints were turned over to the L.A. County Department of Animal Care and Control and its major crimes unit, Sakach said.

He said his organization learned in 2007 the property had been the site of a search warrant and 2,700 birds were seized.

“It appears after that initial one was shut down they started back up even bigger,” said Perry, adding that his department believes the site is primarily being used for breeding, raising and selling the animals to buyers in Los Angeles and neighboring counties.

Perry said the property has had the same owner since the previous search warrant. Sakach defined cockfighting at the news conference as “two roosters being forced to fight to the death often with at least one or both birds dying a violent, agonizing death.”

It’s a problem beyond Santa Clarita, where tens of thousands of dollars are waged at cockfighting events and exchanged through illegal bird sales throughout the country, said Kimberly Abourezk, deputy district attorney and animal cruelty case coordinator for the L.A. County District Attorney’s Office.

In general, Sakach estimates that birds can sell for between $75 and $150. On cockfighting websites, prices can range from $250 to $1,000. And a bird with a winning reputation can fetch more than four figures, Sakach said.

Perry recommended people call their local law enforcement agency, Humane Society or Society for the Prevention of Cruelty to Animals if they know of similar crimes.