WASHINGTON (AP) — A U.S. missile smashed a disabled spy satellite that was headed for earth and the military is tracking the debris as it falls over the Atlantic and Pacific oceans, the Pentagon said Thursday.

Marine Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, told a Pentagon press conference Thursday that he couldn't rule out that hazardous material would fall to the earth.

"Thus far we've seen nothing larger than a football," he said.

Cartwright said officials also "have a high degree of confidence" — though are not ready to say for sure — that the missile launched from a Navy ship near Hawaii on Wednesday struck the satellite's fuel tank. Officials said the toxic hydrazine fuel in the tank would have caused a hazard had it fallen to earth.

The military concluded that the missile had successfully shattered the satellite because trackers detected a fire ball, which seemed to indicate the exploding hydrazine in the tank. A vapor cloud also suggested the destruction of the fuel, he said.

He said officials are 80 percent sure that the tank was breached and the hazardous material was vented off.