UPDATE 1-Sunoco removes 4 staff on unauthorized bidding

NEW YORK, July 9 (Reuters) - Sunoco Inc., the No. 2 independent U.S. oil refiner, said it suspended four employees after they took unauthorized actions in a bidding process.

Philadelphia-based Sunoco said in a statement it has commenced an internal investigation of the employees, who were placed on administrative leave pending resolution of the matter. It said it also reported their actions to the U.S. Department of Justice, which opened its own investigation.

A company spokesman declined to name the employees or give the date when the actions took place. The Justice Department did not immediately respond to a phone call for comment.

"Sunoco does not currently believe the matter will result in any material liabilities or revision of financial statements," according to a statement.

Sunoco said the four employees hail from the crude oil supply, product trading and wholesale distribution branch. The spokesman declined to name them.

Sunoco immediately withdrew from a bidding process for a crude oil processing transaction following the breach of its company policies, the spokesman said.

Sunoco, which has 825,000 barrels of refining capacity, is a relatively new and uncommon participant in such transactions. Generally, a bidding process for a crude oil processing transaction involves a refiner and an oil producing company.

The refiner agrees to take a cargo of crude oil from a producer, then process it into fuel and returns most of the refined product to the oil producer. In exchange, the refiner typically receives a processing fee and keeps some of the refined product.

Sunoco's announcement came less than a week after PVM Oil Futures Ltd., a major global crude oil broker, said it dismissed London-based Senior Broker Steve Perkins for unauthorized trading in crude oil contracts.

(Reporting by Joshua Schneyer and Matthew Robinson)