The U.N. Security Council has voted unanimously to end the mandate for NATO's mission in Libya, despite calls from Libyan officials for the mission to be extended.

The 15-member council on Thursday said the mandate will terminate at the end of October 31 .

Seven months ago, the Security Council authorized NATO to enforce a no-fly zone and take “all necessary measures” to protect Libyan civilians from government forces as then-leader Moammar Gadhafi moved to crush a growing uprising against his rule.

Libya's interim leaders, citing security concerns, urged NATO to continue the mission until at least the end of the year.

In other news, Libya's National Transitional Council said Thursday it will prosecute the killers of Gadhafi if an investigation shows he was killed after his capture by fighters for the provisional government.

NTC leaders have been under intense pressure to investigate the circumstances of Gadhafi's death last week after initially saying he was killed in crossfire after being pulled from a drainage pipe.

Video showing a wounded Gadhafi in the custody of revolutionary forces has raised concerns about the manner of his death as anti-Gadhafi fighters took over his hometown of Sirte.

Libya's Deputy U.N. Ambassador Ibrahim Dabbashi said Wednesday that initial reports show no transitional fighters shot at Gadhafi after he was arrested. Dabbashi told the U.N. Security Council the ousted leader was bleeding from his abdomen and head when he was arrested, and that he died after arriving at a hospital in Misrata.

Separately, a lawyer representing Libya's former prime minister Al-Baghdadi Ali al-Mahmoudi said he has been freed by a Tunisian court.

Mahmoudi fled to Tunisia after Gadhafi's regime collapsed in August, and was recently arrested while trying to cross into Algeria. He went on a hunger strike to protest his possible extradition to Libya.