Craig Morgan's 19-year-old son Jerry Greer is still missing following a water tubing accident on Sunday (July 10), but officials are keeping search crews in the area where the teenager was last seen.

Greer -- one of Morgan and wife Karen's four children, who recently graduated from Dickson County High School -- was tubing with a friend in Kentucky Lake, near Mason's Boat Dock and Marina, located in Waverly, Tenn., when they fell into the water. Although both parties were wearing life jackets, Greer never resurfaced.

"There's always hazards in the area that could've contributed to this accident," Humphreys County Sheriff Chris Davis says (quote via the Tennessean), though there was no collision involving the boat pulling Greer and his friend.

After the search for Greer began on Sunday afternoon, five boats worked the water overnight, and a full-scale search resumed at 6AM on Monday. Davis says about 20-30 boats are now involved in the search, and rescue teams have asked the boater who was pulling Greer's tube for help; they are hoping he can point them to the specific spot that the teenager went missing.

"The family is grateful for everyone’s support and prayers and requests privacy during this difficult time," a statement from Morgan's representatives reads. A candlelight vigil originally planned for Monday night at the Dickson County High School stadium has been cancelled out of respect for the family.

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