On board was enough weapons-grade uranium to make three nuclear bombs, CBS News correspondent Bob Orr reports.
The spent fuel rods were .
In a tape obtained exclusively by CBS News, U.S. scientists can be seen locking at the highly-enriched material in shielded blue transfer tanks.
Will Tobey is in charge of the effort to keep nukes off the black market. He works at the National Nuclear Security Administration for the Department of Energy.
"This material in the hands of terrorists could pose a serious threat," Tobey said.
In the past three years, Department of Energy nuclear swat teams have safely locked up enough material to make 34 nuclear bombs. Most of it collected from former Soviet bloc countries in Eastern Europe and some from countries as far away as Libya and Vietnam.
They've also secured 555 other sites containing enough raw radiological material to build 8,500 so-called "dirty bombs."
"We know that there are those that are bent on trying to obtain this material, equally, we are determined that they won't, and we working every day to make this material more secure," Tobey said.
Just 12 days ago, police in Slovakia, recovered a pound of uranium powder and charged three people with trying to sell it.
Last year a man was arrested in the former Soviet Republic of Georgia carrying a few ounces of weapons-grade uranium.
And those are not isolated incidents. In 2006, there were 250 reports involving the unauthorized possession or theft of nuclear material.
"If a nuclear device went off, you're talking about devastation that is far, far beyond what we aw on September 11," FBI Director Robert Mueller said.
But, this is first line of defense: Nuclear agents working to lock down the world's scattered stockpiles in forgotten, but still-dangerous hot spots.