Libya is a collecting point for many refugees before they attempt the risky crossing of the Mediterranean to Europe.
In November, the African Union Commission painted a bleak picture, saying between 400,000 and 700,000 migrants are living in camps in Libya, often under "inhuman" conditions.
Merkel said Thursday she emphasized in meetings in Berlin with Libyan Prime Minister Fayez Serraj that this "shocking picture" of suffering needed to be improved.
He says a commission is investigating but in the meantime abuses "contradict Libyan culture and we will not tolerate them."
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