The arrests this week of a Little League coach, a registered nurse and a teacher during the largest coordinated raids on dogfighting in U.S. history confirm the shadowy blood sport is alive and well despite tough laws across the country.

More than 400 dogs, including some about to give birth to puppies, were rescued in the raids by federal, state and local authorities Wednesday and Thursday in six states: Missouri, Illinois, Texas, Oklahoma, Iowa and Mississippi, officials said.

U.S. attorneys in several states accused 26 people of cruelties that included shooting dogs in the head when they didn't fight well, then throwing their carcasses into a river or burning them in a barrel.

The sport, often carried out in back alley garages or rural barns, has come under renewed scrutiny after National Football League star Michael Vick was sentenced to prison after his 2007 dogfighting conviction. Dogfighting is a felony in all 50 states, and in recent years, the federal government made it a felony to train, possess or fight dogs.

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But that hasn't stopped people from participating in the sport. Wayne Pacelle, president and CEO of the Humane Society of the United States, said the public can "definitely expect more" arrests and raids, because "dogfighting remains a distressingly widespread activity."

During raids on Wednesday in Texas, federal authorities seized nine pit bulls in rural Panola County and charged nine people, including a 34-year-old Little League coach, with involvement in an interstate dogfighting ring.

Karl Courtney, of the eastern Texas town of Beckville pleaded not guilty, said his attorney David Moore, who described his client as a "well-respected business owner." His brother, Chase Courtney, 26, of the nearby town of Carthage, also was arrested, but a phone number or attorney for him could not be found.

Cris Bottcher, a 48-year-old registered nurse at a community hospital in Bethany, Missouri, also was arrested Wednesday in western Missouri and accused of shooting underperforming dogs and putting their carcasses in plastic containers outside a garage, according to a federal indictment.

Six others were also arrested in that raid including Rick Hihath, a 55-year-old physical education teacher at a state school for the severely disabled, the indictment said. He is accused of working and promoting fights at Bottcher's farm, it said.

The Missouri men were due in court Friday, said Don Ledford, a spokesman at the U.S. Attorney's office in Kansas City, Missouri. Their court-appointed attorneys did not return phone calls, and people who answered the phones at their homes declined to comment.

Randall Lockwood, an animal behaviorist working with some of the dogs in a St. Louis shelter, said the arrests illustrate dogfighting's prevalence.

"It's a very long battle and the battle will continue as long as people cause suffering and death for financial gain and amusement," said Lockwood, of the American Society for the Prevention of Cruelty to Animals.

Authorities are closely guarding the condition of the rescued dogs because of the pending criminal trials. The Humane Society of Missouri said it is housing most of them at its emergency shelter in St. Louis. Groups in Texas, Oklahoma, Mississippi and Iowa are taking care of another 75 to 100 dogs, the Missouri group said.

"We're seeing a lot of tail wags," said Janell Matthies with United Animal Nations, a California nonprofit rescue group assisting in the dogs' medical triage.