HOUSTON, March 24 (Reuters) - No evidence has been found of a deliberate act as the cause of a Monday night explosion at Valero Energy Corp's (VLO.N), opens new tabPort Arthur, Texas refinery, said the spokesperson for the Jefferson County Sheriff's office on Tuesday. No evidence Valero Texas refinery blast caused by intentional act, sheriff's office | Reuters Skip to main content Exclusive news, data and analytics for financial market professionalsLearn more aboutRefinitiv Companies Valero Energy Corp Foll ...