WASHINGTON (CNN) -- Blackwater USA guards have used deadly force weekly in Iraq and have inflicted "significant casualties and property damage," according to a congressional staff report released Monday that cites internal company and State Department documents. Blackwater's contractors fired their weapons 195 times -- or an average of 1.4 times a week -- from the beginning of 2005 through the second week of September, the Democratic staff of the House Oversight and Government Reform Committee found. In over 80 percent of the cases, Blackwater reports that its forces fired first, according to the staff report. The committee will hear from Blackwater's CEO Erik Prince on Tuesday. Read Prince's prepared statement (PDF)
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Report: "Vast majority of Blackwater weapons discharges are pre-emptive"
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Report is based on Blackwater and State Department internal documents
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Sources: Contractor wrote U.S. "spot report" on September shooting
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State Department: Report is "first-blush account" with "no standing"
A @placeholder agent took sworn statements from the participants in the shooting after receiving the spot report, the embassy source said.