By CBSBoston.com Staff

SOMERVILLE (CBS) – A Somerville man accused of fatally shooting his roommate is being held without bail pending a dangerousness hearing.

Investigators said 26-year-old Edson Moreno shot 22-year-old Robert Favreau after an argument Wednesday night.

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Police responded to a home on Ware Street at about 5:45 p.m. and found Moreno outside with a gun. He was arrested after he put the gun on the ground.

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Favreau, who had been staying in the home for several months was found dead inside with an apparent gunshot wound and pronounced dead at the scene.

A woman who witnessed the shooting hid in a closet and called 911.

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Moreno was arraigned Thursday on charges including armed assault to murder. Investigators say more charges are expected.

CBSBoston.com Staff