US officials have broadened their probe into BP's commodity trading activities.
A regulatory filing made by BP revealed that the US Department of Justice (DoJ) has joined the US Commodity Futures Trading Commission in looking into the group's trading activities. It is researching the company's oil trading and storage activities going as far back as 1999.
Previously BP had said that just the CFTC was carrying out an investigation, with probes going back only as far as 2002.
The energy company said that it was cooperating with "various formal and informal requests for information".
BP has previously been hit with a $100,000 fine from the CFTC, after one of its traders was accused of being involved in "wash trades" in 2000. It has previously been the subject of three probes in the US since June 2006 for allegedly manipulating propane, crude oil and petrol prices between 2002 and 2004.
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