Some Muslim servicemembers are worried that the mass shooting at Fort Hood could unravel their work to be accepted as loyal, dedicated soldiers.

Witnesses have told investigators that Maj. Nidal Malik Hasan shouted "Allahu akbar!" _ the phrase that means "God is great!" in Arabic _ before opening fire in a rampage that left 13 soldiers dead. While a motive in the attack isn't clear, Hasan had complained to family members of discrimination.

Many Muslims who serve in the military say they are accepted by their comrades. But Army Chief of Staff George Casey said this week he worries about backlash.

Muslim veterans and soldiers say that snide comments are made about their faith sometimes, but officers take allegations of discrimination seriously.