The 155-mm shells containing sarin gas that exploded in Iraq May 17 were manufactured before 1991, a senior U.S. official said Wednesday. That was a pre-Gulf War shell, a different category than the weapons being sought by the Iraq Survey Group, Brig. Gen. David Rodriguez, the joint staff deputy director for operations, told a Pentagon news briefing.

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For what it's worth in the debate over the shells.

Sarin Shells Made Before 1991 War