SALT LAKE CITY—The nation's largest chemical weapons depot has destroyed its final stockpile of nerve agent -- a 4,100-pound supply seized by U.S. troops from Nazi Germany.

The Deseret Chemical Depot says the Nazi nerve agent had been stored in bulk containers since the end of World War II.

The Army depot in Utah's west desert is ending a 15-year campaign of destroying a variety of chemical weapons.

Only small supplies of other chemical agents remain to be incinerated, and that job is expected to be completed by early next year.

The stockpiles are being destroyed under an international treaty to rid the world of chemical weapons.

The Deseret Chemical Depot, 45 miles southwest of Salt Lake City, once held more than 40 percent of the nation's chemical weapons.

© Copyright 2011 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.