A carnival ride operator facing assault charges over injuries from a ride at the North Carolina State Fair made his first appearance in court Monday, with a prosecutor saying there are still unanswered questions about what happened.

Timothy Dwayne Tutterrow, 46, of Quitman, Ga., faces 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 Sheriff Donnie Harrison said investigators determined the ride had been intentionally tampered with to bypass critical safety devices, though authorities have provided no details of the evidence against Tutterrow.

The "Vortex" jolted into motion Thursday evening as people were exiting, dropping riders from heights eyewitnesses estimated at up to 30 feet.

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