Three Navy fliers were killed when their jet crashed about 50 miles west of Spokane, Wash., on Monday, officials said.
The fliers were on a training mission on an EA-6B Prowler based at Naval Air Station Whidbey Island, on Washington's Puget Sound.
No one on the ground was hurt, Navy officials said. The fliers' names are to be kept confidential for a day while their families are notified, officials said.
A farmworker, Mike Johnson, told the Spokesman-Review newspaper that he was feeding cattle shortly before 9 a.m. when he saw a black mushroom cloud rise soundlessly in the distance. The crash left a black crater and a fan of debris in a field.
The Prowler, which seats four, is a 60-foot-long, twin-engine anti-radar jet developed by Northrop Grumman Systems Corp. The jet, first deployed by the military in 1968, commonly serves as protection for other aircraft by jamming enemy radar.
But the Prowler's design is aging, and the military's Prowler fleet is being phased out in favor of the two-seater $90-million EA-18G Growler, another anti-radar jet.
Whidbey Island is home to the Navy's so-called tactical electronic squadrons that fly both models. The downed Prowler was assigned to the Electronic Attack Squadron 129 (VAQ-129), dubbed the "Vikings" squadron.
Whidbey Island is home to a memorial for aircrew and maintenance personnel killed in Prowler accidents.
"The thoughts and prayers of northwest Washington are with the families of the aircrew who lost their lives today," Rep. Rick Larsen (D-Wash.), the top Democrat on aviation for the House Transportation Committee, said in a statement.
"I grieve with Whidbey Island for the loss of three of our own," Larsen said. "This tragic crash is a painful reminder of the dangerous work that members of the armed services perform every day in service to our nation."