tripoli libya u.n.-backed government say thursday investigate report african migrants sell slave promise bring perpetrators justice footage broadcast cnn appear show african migrants trade libya spark international outcry protest europe africa direct instructions issue form investigative committee uncover truth capture wrongdoers responsible put judiciary libyan interior minister aref al-khodja tell journalists tripoli currently wait result investigations believe come close cnn video show say auction men offer libyan buyers farmhands sell 400 appear confirm early report existence market trade migrants libya many libyans react anger outcry point european push stop migrants cross mediterranean italy activists say result worsen condition migrants inside libya call local international body cooperate attorney general office provide information help reveal truth u.n.-backed government presidency say statement libya victims illegal migration source add appeal foreign power help stop flow migrants countries origin across libya southern border u.n. libya mission say wednesday actively pursue matter libyan authorities set transparent monitor mechanism safeguard migrants horrific human right abuse pressure italy u.n.-backed government co-opted local group try bolster libya coastguard stem record flow migrants cross mediterranean since 2014. though sea arrivals italy almost third year week mark surge rescue several days bad weather one body recover italy coast guard humanitarian group say wednesday 1,100 migrants rescue 11 boat coast guard say 200 pick thursday libyan government say investigate migrant 'slave market report