(CNN) -- A top defector from the Syrian military said Saturday that armed rebel groups have aligned under the leadership of the Free Syrian Army. Uniting all efforts will bolster the anti-regime movement and safeguard the nation, Brig. Gen. Mustafa Sheikh said in a video posted on YouTube. The move addressed a key concern for observers of the Syrian crisis both inside and outside the country -- that armed rebel groups were disjointed and divided. Sheikh was one of the first high-ranking officers to announce his defection from President Bashar al-Assad's forces. He was accompanied in the video by Free Syrian Army commander Col. Riad al-Asaad.
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At least 54 people are killed Saturday, activists say
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The unification helps dispel notions of a disjointed rebel movement
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Second, with the FSA serving and protecting @placeholder, "any movement to carry out a military operation or do anything outside the framework of the FSA "will be held responsible for any act they carry out," Sheikh warned.