Mark Dickey’s partner and fellow caver Jessica Van Ord was with him when he began suffering gastrointestinal bleeding more than 1,000m below ground in the Morca cave complex on 2 September, according to Reuters.
Ms Van Ord remained by Mr Dickey’s side as an Italian rescue team with medical personnel reached the 40-year-old New Yorker and gave him IV fluids and blood inside the cave.
She has been staying at a base camp near the mouth of the cave, and working with the 150-strong team of cavers who have travelled to Turkey to help bring Mr Dickey out by stretcher.
On Sunday, the Speleological Federation of Turkey wrote on X/Twitter that rescue teams had brought Mr Dickey to 500m below the surface just after 7pm local time (2pm EST).
“Half of the rescue distance is over,” the federation wrote.
The operation began on Saturday afternoon with doctors, paramedics and experienced cavers began carrying Mr Dickey on a stretcher from a depth of just below 1,000m.
Medical base camps were set up along the shaft, where the stricken caver could rest during the slow and arduous extrication.
Turkish authorities said 190 personnel from eight countries were taking part in the operation, which is expected to take up to 10 days.
Mr Dickey thanked the Turkish government and rescuers in a video message on Thursday.
Prior to embarking on the expedition, Mr Dickey posted several photos on Facebook with Ms Van Ord showing the pair making last-minute preparations.
“Caving Academy gear being inspected and marked before heading off to the MORCA expedition,” Mr Dickey wrote on 13 August.