Warren Resources Inc. (Nasdaq: WRES) announced that it has closed the purchase and sale transaction under the previously announced agreement to acquire certain additional natural gas and midstream assets from subsidiaries of Anadarko Petroleum Corp. in the Atlantic Rim project area in the Washakie Basin, Wyo. By exercising its preferential rights and closing this transaction with Anadarko:

• Warren acquired 79% of Anadarko's working interest in the Spyglass Hill unit area within the Atlantic Rim Project, representing approximately 37,142 net leasehold acres and an approximate 32.8% additional total unit working interest therein, for a purchase price of $11.4 million, which increased its working interest in the entire unit from 30.1% to 62.9%.

• Warren also acquired 26.5% of Anadarko's interest in the Catalina unit area within the Atlantic Rim project, representing approximately 1,121 net leasehold acres and an approximate 5.2% additional total unit working interest therein, for a purchase price of $0.7 million, which increased its working interest in the entire unit area from 16.9% to about 22%. With this acquisition, Warren's working interest in the currently producing Catalina unit PA increased from approximately 8% to 12.5%.

• Lastly, Warren acquired 100% of Anadarko's 50% interest in the gas gathering, compression and pipeline midstream assets within the Atlantic Rim project for a purchase price of $4 million. The midstream assets consist of gathering and compression equipment and a 59-mile long pipeline that transports gas from the gathering systems throughout the Spyglass Hill unit area to the Wyoming Interstate Co. interstate gas transportation pipeline.

As a result of the transaction, Warren's estimated proved developed reserves in the Atlantic Rim increased by approximately 18.3 Bcf. Additionally, the acquisition will add natural gas production of about 7.8 MMcf/d.