The cause of the rupture and the total volume of oil released after the North Dakota spill remain unclear, officials said.

The nearly 2,700-mile Keystone oil pipeline was shut down Tuesday morning after it ruptured in North Dakota, halting the flow of millions of gallons of crude oil from Canada to refineries in the U.S.

The owner of the Keystone pipeline issued a force majeure notice to companies that ship oil on the conduit after a leak in North Dakota on Tuesday released an estimated 3,500 barrels.

The Keystone oil pipeline was shut down Tuesday morning after it ruptured in North Dakota, with the spill confined to an agricultural field.

A portion of the Keystone oil pipeline has ruptured, forcing it to be shut down in North Dakota. It is not known what caused the break and the amount of crude oil that flowed into an agricultural field in Fort Ransom,

Officials shut down Keystone oil pipeline in North Dakota after a rupture leads to the release of oil. About Contact Services Account

The latest leak in the Keystone oil pipeline in North Dakota on Tuesday continues the troubled history of the 15-year-old pipeline

The Keystone oil pipeline was shut down Tuesday morning after it ruptured in North Dakota, halting the flow of millions of gallons of crude oil from Canada to refineries in the U.S.

According to the North Dakota Department of Environmental Quality, there was a malfunction of the pipeline near Fort Ransom that caused oil to spill into a nearby field south of a pump station. A small stream near the site has been isolated and remains unaffected at this time,