Omaha, NE (AP) - Opponents of a Canadian crude oil pipeline have made good on their threat to challenge Nebraska's new pipeline siting law in court.

The lawsuit filed Wednesday by several Nebraska landowners along TransCanada's proposed pipeline route argues that the law outlining the review process is unconstitutional.

The pipeline opponents say the law doesn't allow for judicial review and doesn't spell out what criteria should be considered when a proposed pipeline is being evaluated.

The Nebraska Attorney General's office declined to comment on the lawsuit because it had not received a copy of it.

TransCanada's proposed Keystone XL project is designed to carry oil from Canada across Montana, South Dakota, Nebraska, Kansas, Oklahoma and Texas. TransCanada also has proposed connecting it to the Bakken oil field in Montana and North Dakota.

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