Aug 31 (Reuters) - InterOil Corp IOC.N :
* Drilling operations underway at Antelope-4 st1
* Started drilling side-track well at Antelope-4 site, as part of its appraisal
campaign on the Elk-Antelope gas field in Papua New Guinea
* Source text for Eikon ID:nPn3JTHpR
* Further company coverage IOC.N