WASHINGTON (AP) — Lawyers for Blackwater security guards are accusing the government of suppressing evidence favorable to the defendants, who are accused in the killings of 14 Iraqis in Nisoor Square in Baghdad.

The attorneys say the suppressed evidence consists of photographs of eight spent shell casings that would fit an AK-47 — the weapon of choice used by insurgents and Iraqi authorities.

A court filing by the defense attorneys says the photographs were taken by a U.S. Army captain and that they never saw the light of day until federal prosecutors turned them over last Wednesday.

The photos could become an important part of the case. They might bolster the accounts of the security guards, who say they were being fired upon by insurgents and that the guards were simply returning fire.

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