WASHINGTON (AP) — House Democrats say a Republican-led investigation into the deadly attack against the U.S. diplomatic mission in Benghazi, Libya, is a partisan "witch hunt," and they're demanding that it end.

Two congressmen — Adam Smith of Washington state and Elijah Cummings of Maryland — tell reporters that multiple inquiries and reports have answered the questions surrounding the Sept. 11, 2012, assault.

Four Americans, including U.S. Ambassador Chris Stevens, were killed.

Smith says Republicans continue to press ahead in a partisan attempt to embarrass the Obama administration. Cummings says the GOP is engaged in a game of "political gotcha."

Republicans, who control the House, insist there are unresolved issues and they have a responsibility to fulfill their oversight role.

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