Military officials are investigating a "large balloon and payload" discovered by fishermen off the coast of Alaska last week, the Department of Defense confirmed on Friday.

"A U.S. commercial fishing vessel recovered portions of … what appears to be a large balloon and payload caught in their nets while fishing off the coast of Alaska," Sue Gough, a spokesperson for the Defense Department, said in an email.

The agency would not characterize the balloon as a spy or surveillance device.

The fishermen first reported the discovery to the Coast Guard, who asked them to hold the materiel on board until it could be collected by officials upon the boat's return to port, Gough said.

In a statement, the FBI said it was aware of debris found off the coast of Alaska by a commercial fishing vessel and assisted partners in debris recovery.

They had no further comment as of Friday afternoon.

The balloon is currently being analyzed at Joint Base Elmendorf-Richardson, around 9 miles northeast of Anchorage. Officials do not know what the balloon was doing off the coast of Alaska, but hope to learn more through an analysis of the materiel, which will be carried out by multiple agencies, Gough said.

More:Military officials say small balloon spotted over Western U.S. poses no security risk

Chinese balloon shot down last year triggered diplomatic rift with China

The appearance and takedown of a Chinese spy balloon drifting over the U.S. last year propelled the issue to international attention.

The balloon was first spotted floating over the Aleutian Islands in Alaska in late January of last year, according to the Pentagon. It drifted through Canada before entering U.S. airspace in Idaho and continuing eastward.At 11 miles above ground, it flew high enough to avoid interfering with commercial air traffic, defense officials said.

It was finally shot down off the coast of South Carolina on Feb. 4 by a missile fired from an F-22, the military's most sophisticated warplane. President Biden first gave the order to shoot it out of the sky three days earlier while the balloon was above land, but Pentagon officials feared the debris could endanger people on the ground.

The balloon triggered a diplomatic rift with China that prompted Secretary of State Antony Blinken to cancel a planned trip to Beijing. The balloon had passed over some sensitive military sites, including facilities holding nuclear weapons and missiles in Montana, according to the State Department. U-2 spy planes sent to examine the balloon in mid-air found that it was equipped with devices to collect "signals intelligence," officials said.

China denied that the balloon had espionage capabilities, calling it a "civilian airship" that had been blown off course over the U.S. while conducting weather research, and apologized for its "unintentional entry" into U.S. airspace.

The military launched a major operation led by the Navy's Explosive Ordnance Disposal Group 2 to collect the balloon from the water after it was downed. Air Force Gen. Glen VanHerck said the balloon was 200 feet tall and weighed around 2,000 pounds – the size of around three buses.

Military officials revealed that the Pentagon was aware that suspected Chinese spy balloons had entered U.S. airspace three times during the Trump administration and once afterwards.

Cybele Mayes-Osterman is a breaking news reporter for USA Today. Reach her on email at [email protected]. Follow her on X @CybeleMO.