Yellowstone River oil leak: Aerial view

An oil pipeline that runs under the Yellowstone River in the US state of Montana has ruptured, leaking crude oil into the river.

Oil giant ExxonMobil said the pipeline, which runs from Silver Tips to Billings, had been shut down and the spill isolated.

Nearby residents were evacuated from their homes but were later allowed to return.

Billings' Wildlife and Parks Programs Manager, Bob Gobson, says contact with the oil could be fatal for fish living in the river.