(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 division is over," a rebel leader says as rival army defectors unite
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The unification helps dispel notions of a disjointed rebel movement
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Special envoy Kofi Annan will discuss the crisis with Russia and China
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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.
Mustafa Sheikh
Sheikh
"This man represents himself," al-Asaad said of @placeholder last month.