Denmark’s Nicole Broch Larsen is one shot further back in third position while China’s Shanshan Feng is alone in 4th.
A winner of one LPGA Tour event, Lee has a good record in major championships without necessarily contending but has opened up the possibility of yet another Korean major winner.
New Zealander Lydia Ko is five shots from the lead in a share of 5th position while Minjee Lee heads the Australians in 15th position and seven shots from Lee.
World number one Inbee Park improved with a round of 69 today but is eight shots from the lead in 20th place.
Karrie Webb (45th) and Sarah Kemp (57th) were the other Australians to make the cut.
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