Jakarta, Dec. 2 -- The Corruption Eradication Commission (KPK) issued a summons to four witnesses over investigation into a bribery case linked to crude oil trade and refinery products at Pertamina Energy Services (PES) Pte Ltd on Monday.

The four will face questioning as witnesses in the case against the PES Pte Ltd managing director, identified by his initials as BI, named a suspect in the case.

"Today, (the KPK) is scheduled to question four witnesses in a bribery case related to crude oil trade and refinery products at Pertamina Energy Services (PES) Pte. Ltd.," KPK spokesman Febri Diansyah stated.

The four witnesses are Manager of Project Management Office-Shared Service Center of PT Pertamina (Persero), formerly manager controlle...