WASHINGTON (Nexstar) – On Tuesday, senators got a briefing on the objects that were shot down after flying over the U.S. – during which they heard that the first balloon was different from the other three objects.

Senators say three of the four flying objects recently shot down by the U.S. remain unidentified.

“They’re lost, they can’t find them. The remnants are in very difficult terrain,” Sen. John Kennedy (R-LA) said.

Both Republican and Democrat senators received a classified briefing about the objects and say they learned the phenomenon isn’t new.

“These objects have been flying over us for years,” Sen. Kennedy said. “We’ve known about those objects for many years.”

Florida Senator Marco Rubio says what is new, is the U.S. response adding, “that they were shot down, which is extraordinary. We’ve never shot down anything in over 65 years of NORAD.”

The Biden administration says it shot down the latest three objects faster than the first because they were in commercial airspace.

“If you are going to function in commercial airspace you have to have emitters, you have to have lights,” Sen. Kirsten Gillibrand (D-NY ) said.

Additionally, Gillibrand says those objects weren’t following protocols and were different than the first object, which the government says is a Chinese spy balloon.

“It was very different in nature than the other three objects that were shot down and it was different in how it moved,” Gillibrand said.

Many Republicans say they want President Biden to personally brief the public on the unidentified flying objects.