RALEIGH, N.C. — A ride that jolted into motion at the North Carolina State Fair, injuring five, had been intentionally tampered with to bypass critical safety devices, a sheriff said, with the ride operator accused of assault in an investigation that a prosecutor said could yield more charges.

Timothy Dwayne Tutterrow, 46, of Quitman, Ga., made his first court appearance Monday to face three counts of assault with a deadly weapon, inflicting serious injury. Each count is punishable by up to eight years in prison.

Wake County District Court Judge Keith O. Gregory declined a request during the brief hearing to lower Tutterrow’s $225,000 bond. The defendant, dressed in an orange and white striped jumpsuit, was taken back to jail in handcuffs.

Wake County Sheriff Donnie Harrison said investigators determined the ride had been intentionally tampered with, though authorities have provided no details of the evidence against Tutterrow.

The “Vortex” started moving Thursday evening as people were exiting, dropping riders from heights eyewitnesses estimated at up to 30 feet.

Three people were hospitalized Monday with serious injuries, including a 14-year-old. Two others were treated and released.

Wake County District Attorney Colon Willoughby said in court he would personally handle Tutterrow’s prosecution.

“There are still some unanswered questions we are trying to get to the bottom of,” Willoughby said. “These are very serious charges and we want to make sure we are proceeding in the right way.”

Tutterrow’s lawyer, Roger W. Smith Jr., said Sunday his client is a loving husband and father.

“It is such a tragedy what happened and he’s just reeling from that,” Smith said. “He’s devastated and distraught.”