In this July 9, 2014, file photo, riders go down the water slide called "Verruckt" at Schlitterbahn Waterpark in Kansas City, Kan. (AP Photo/Charlie Riedel, File)

Kansas City, Mo. — A Kansas water slide hyped as the world’s highest was a “deadly weapon” that had already injured more than a dozen people before a 10-year-old boy was decapitated on it in 2016, according to a grand jury indictment unsealed Friday that charges the water park operator and an executive with involuntary manslaughter.

Operators of the Verrückt water slide at the Schlitterbahn Waterpark in Kansas City, Kan., also knew that the raft Caleb Schwab and two women used during the deadly accident was prone to moving faster and becoming airborne more than others. It was removed twice in 2016 but quickly put back into circulation, the indictment says.

“The ride was never properly or fully designed to prevent rafts from going airborne,” the indictment said.

The water park and Tyler Austin Miles, 29, a former operations director at the park, were indicted Friday on involuntary manslaughter and several other charges in Caleb’s death. The indictment alleges that a company co-owner and the designer of Verrückt rushed it into use and had no technical or engineering expertise related to amusement park rides.

The charges come after a 19-month investigation into the death of Caleb, the son of Kansas Rep. Scott Schwab. The raft Caleb was in went airborne, hitting a pole and netting designed to keep riders from being thrown from the ride.

The indictment says a video shows Caleb was following all rider instructions when he died.

The death seemed like an isolated accident until whistleblowers from Schlitterbahn revealed that experts who examined the slide found evidence indicating other rafts had gone airborne and collided with the overhead hoops and netting before the fatality, according to the indictment.

The ride complied with “few, if any” longstanding safety standards established by the American Society for Testing and Materials, and corporate correspondence found that “the child’s death and the rapidly growing list of injuries were foreseeable and expected outcomes,” according to the indictment.

Investigators found 13 injuries to others during the 182 days the ride operated, including two concussions and one case where a 15-year-old girl went temporarily blind.

A spokeswoman for Schlitterbahn did not immediately return a request for comment after the indictment against the company was unsealed.

The other charges in the indictment include aggravated battery and aggravated endangerment of a child. Miles was indicted on two counts of interference with law enforcement and Schlitterbahn was indicted on one count of interference with law enforcement.

The indictment says Schlitterbahn co-owner Jeffrey Wayne Henry decided in 2012 to build the world’s largest water slide to impress the producers of a Travel Channel show, and that Henry’s desire to “rush the project” and his and his designer’s lack of expertise caused them to “skip fundamental steps in the design process.”

The indictment also said not a single engineer was directly involved in Verrückt’s engineering or slide path design.

Miles pleaded not guilty Friday during a brief court appearance. His attorneys asked that his bond be reduced to $15,000 from $50,000 but that request was denied. A trial was scheduled for Sept. 10.

Investigators are alleging that Miles avoided or delayed repairs that would have taken Verrückt out of commission during the active park season, and that the ride’s brake system failed 10 days before Caleb’s death. Miles also is accused of telling a police detective that he was unaware of any complaints about the ride and of withholding “thousands” of incriminating daily reports from lead lifeguards and supervisors.

Schlitterbahn, which is based in Texas, said in a statement after charges against Miles were announced that it was “deeply disappointed to learn any individual is being personally charged for the terrible accident on Verrückt.

“Our review of the facts and circumstances of the accident has never shown any evidence of criminal conduct on the part of anyone,” spokeswoman Winter Prosapio said.

Scott Schwab and his attorney, Mike Rader, didn’t immediately respond Friday to a request for comment.

The water slide has been closed since Caleb’s death. Schlitterbahn has said it will dismantle the ride when the investigation into the boy’s death is complete.

Caleb Schwab’s family reached settlements of nearly $20 million with Schlitterbahn and various companies associated with the design and construction of the water slide. The two women who rode with Caleb suffered serious injuries and settled claims with Schlitterbahn for an undisclosed amount.

Before the boy’s death, Kansas law allowed parks to conduct their own annual inspections of rides. Lawmakers last year nearly unanimously approved stricter, annual inspection requirements for amusement park rides that set qualifications for the inspectors and required parks to report injuries and deaths to the state.

But only weeks later, lawmakers passed a follow-up bill delaying the enforcement of criminal penalties for operating a ride without a state permit until this year. And this year, the Senate and a House committee have approved legislation to lessen regulation for “limited use” rides at events like county fairs and exempt some amusements, such as hay rides, from regulation.