The company said high gas readings were observed while drilling through the Toro sandstone and the preliminary interpretation of the log data indicated the presence of hydrocarbons.
The second target Giero Sandstone lacked reservoir quality sands.
Korka-1 is about 50 kilometres northwest of the Hides and Angore gas fields and has an estimated mean recoverable resource of 1.3 trillion cubic feet of gas.
The well is being drilled as part of Oil Search's hunt for more gas to underpin its liquefied natural gas expansion plan in PNG.
Oil Search said the well will be drilled to a depth of 3300m before an evaluation program, including formation pressure measurements of the Toro sandstone, is carried out.
"This work will confirm the presence and type of any hydrocarbons present in the formation."
Oil Search holds a 50% interest in PPL 260 following the farm-out of a 20% interest to Nippon Oil. Eaglewood Energy holds the remaining 30%.