A 16-year-old Great Falls girl and a Northeast Washington man drowned Sunday in unrelated incidents in Prince William and Loudoun counties, police said.

Jill Simmons of the 10700 block of Beach Mill Road had been scuba diving with her mother, Clarissa, and a group of youths at the Millbrook Quarry off Rte. 55 near Haymarket when the girl and her mother began to drift toward deeper water, Prince William County police spokesman Sam Walker said.

The diving instructor, Robert Curtis, tried to assist the two, but the girl panicked and removed her mouthpiece, Walker said. She was removed from the quarry after being underwater for about five minutes.

The girl descended 75 feet and was underwater about five minutes. After she was removed from the water, she had no pulse and was not breathing. She died at the Baltimore trauma center after being flown there from Prince William hospital, Walker said.

Leroy Ratcliff, 19, of 619 Dix St. NE was swimming with family members in Festival Lakes about half a mile east of Leesburg when he went under, Lt. Greg Stocks of the Loudoun County Sheriff's Department said. Two state police divers found his body about two hours later in 15 feet of water 25 feet from shore, police said.