UPDATE 1-US CSB to probe Silver Eagle Utah refinery blast

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HOUSTON, Nov 4 (Reuters) - The U.S. Chemical Safety Board was mustering a team of six investigators to begin probing the Wednesday morning blast at the Silver Eagle refinery in Woods Cross, Utah, a board spokesman said on Wednesday.

The board is already investigating a January flash fire at the refinery.

Significant damage to nearby houses and the earlier incident led the board to order the investigation of Wednesday's fire, said CSB spokesman Daniel Horowitz.

The CSB is also probing a fire last month at Tesoro Corp's (TSO.N) Salt Lake City refinery. (Reporting by Erwin Seba)