Some 7,000 people, many of them foreigners, are being held in Libyan detention centers controlled by "revolutionary brigade" militias, The Telegraph said citing a new UN report.

Women and children are among detainees and some have allegedly been tortured, said the report by UN Secretary General Ban Ki-moon ahead of a Security Council meeting on Libya since the death of dictator Muammar Gaddafi.

Political prisoners from the Gaddafi regime have been freed, but the estimated 7,000 new detainees have no access to courts "in the absence of a functioning police and judiciary," said the report.

In a separate statement, Ban welcomed the announcement of Libya's interim government and again said it faces "numerous challenges," including "the crucial issues of national reconciliation, public security, human rights protection, and the resumption of basic services to the Libyan people."