(Adds conflicting report on injuries; BP spokesman says no information immediately available; background on the refinery and BP strategy)
Aug 28 (Reuters) - An explosion shook BP Plc's Whiting, Indiana refinery, its largest in the United States, on Wednesday night but a resulting fire had been contained as of 9:30 pm local time (0230 GMT Thursday), according to a report by WFLD-TV.
Local officials did not know which unit was involved and a BP spokesman said the company was preparing a statement.
There were reports from local media that at least one person was taken to an area hospital. Other reports said no injuries had been reported in the blaze.
Whiting city firefighters were asked by BP to be ready to assist the refinery's firefighting force in battling the blaze, but were not called in to the plant, a fire department spokesman said.
The 413,500 barrels-per-day (bpd) Whiting refinery is BP's largest in the United States and is the centerpiece of the company's shift over the past two years to emphasize using cheaper, heavy crude oil from Canada's tar sands fields in Alberta.
In November, BP completed a $4 billion revamp of the Whiting refinery to boost its intake of Canadian crude oil from 85,000 bpd to 350,000 bpd.
On July 29, BP's Chief Executive Bob Dudley said during a conference call that Whiting refinery had been running 270,000 bpd in heavy crude oil could likely run up to 300,000 bpd. (Reporting by Kristen Hays and Debasis Mohapatra in Bangalore, additional reporting by Erwin Seba in Houston and Eric Johnson in Seattle; Editing by Prateek Chatterjee and Gopakumar Warrier)