TULSA, Okla. (AP) - The chief of staff to newly-elected Republican U.S. Rep. Markwayne Mullin says the congressman and his family have received death threats.

Karl Ahlgren said in a statement Saturday that the threat is being investigated and that Mullin and his family - which includes his wife, two sons and a daughter - are being protected.

Ahlgren said authorities are investigating and that the office will have no further comment.

U.S. Capitol Police Officer Shennell Antrobus said that agency is investigating - but declined comment on what the specific threat is. He said the safety of members of Congress is considered paramount and that all threats deemed credible are investigated.

Mullin was elected congressman from Oklahoma's 2nd Congressional District in November. Incumbent Democratic Rep. Dan Boren did not seek re-election.

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