A skydiving instructor whose parachute did not open during a jump on Saturday has died, according to the Texas center where he worked.

“Skydive Houston, along with the greater skydiving community at large, is deeply saddened by the loss of our tandem instructor and friend,” Skydive Houston skydiving center in Waller, Texas, said in a statement on Sunday. “Our sincerest condolences are extended to his friends and family. We continue to pray for a full recovery for the injured tandem student.”

Waller County Sheriff Troy Guidry told CNN a female skydiving customer and her male instructor were doing a tandem jump Saturday afternoon near the city of Waller, northwest of Houston and “the parachute failed to open.” He added, “The primary and secondary [parachutes] both just kind of swirled down.”

Guidry said Saturday both were flown to Memorial Hermann Medical Center in Houston where they were listed in critical condition on Saturday night.

Guidry said the cause of the accident is under investigation and Skydive Houston said jump operations are suspended pending local law enforcement and FAA investigations. (CNN)