Mitzie Sue "Susan" Clements, an Ohio woman, missing in Great Smoky Mountain National Park, near the border between North Carolina and Tennessee

Authorities are looking for a missing woman from the missing Ohio while she was hiking in Great Smoky Mountain National Park, on the border between North Carolina and Tennessee . Mitzie Sue "Susan" Clements, 53, was with her daughter on Tuesday when they briefly separated. Clements has since disappeared.

The girl walked slightly in front of her mother, but when she returned to join Clements, she was away, National Park Service spokeswoman Julena Campbell told WATE-TV.

Until Sunday afternoon, investigators found no clue or indication of where she was, Campbell told CBS News. She said about 125 people from about 30 different agencies were doing research in different areas, including the peaks and flanks of several mountains.

Crews use K-9 units, helicopters and drones to facilitate searches, Campbell added, adding that missing persons flyers were posted in the area to inform the public of the search. The region has very rough terrain and thick vegetation, she said, making research very methodical.

Clements was last seen with a green zip sweater, a transparent rain poncho, black pants on black leggings and white sneakers, the National Parks Service announced on Facebook.