SALISBURY, Md. -- The cause of death for a Texas woman who died while vacationing in Maryland has been ruled as accidental asphyxia due to suffocation, the medical examiner said.

Officials believe Ashley O'Connor, 30, from Plano, walked alone on an Ocean City beach at about 2 a.m. Monday before she was found in a hole covered by sand later that morning.

"It remains to be determined at this time if O’Connor fell into the hole or climbed in on her own accord," the medical examiner's office said. Experts say sand collapses are a common occurrence in that area, although it's not determined if that's what happened.

O'Connor had been vacationing in the resort town with her family.