Ten environmental groups are suing a federal agency over its approval of drilling permits off Alaska's northwest coast.

The lawsuit seeks a review of permits granted to Royal Dutch Shell PLC by the Bureau of Ocean Energy Management for exploratory drilling in the Chukchi (chuk-CHEE') Sea.

Drilling in the Arctic Ocean region is opposed by environmental groups that contend oil companies are not equipped to deal with a major blowout or spill in a region lacking deep-water ports, major airports and other infrastructure routinely present in other drilling areas.

The groups say the federal agency's review of Shell's exploratory drilling plan was rushed and cursory.

They say the company's drill vessels and an accompanying flotilla of support vessels threaten whales, walruses and seals.

The lawsuit was filed Tuesday in the 9th Circuit Court of Appeals.