Montana : An ExxonMobil spokesman says oil detected 25 miles away ; the state says 50 miles . Long term , and depending on factors like the quantity and nature of the leaked oil , toxins may kill critical insects , which in turn could have a trickle-down effect on the multimillion-dollar fishing industry , he said . Montana declares a state of emergency for 7 counties , saying ExxonMobil is responsible . State officials are unclear of the cause of the spill in Montana 's Yellowstone River . ExxonMobil reports up to 1,000 barrels of oil -- 42,000 gallons -- escaped through a crack .
Montana : An ExxonMobil spokesman says oil detected 25 miles away ; the state says 50 miles . Montana declares a state of emergency for 7 counties , saying ExxonMobil is responsible . State officials are unclear of the cause of the spill in Montana 's Yellowstone River . ExxonMobil reports up to 1,000 barrels of oil -- 42,000 gallons -- escaped through a crack .