Slain Tunisian leader's party to ask for U.N. inquiry

A woman chants slogans and holds pictures of assassinated leftist politician Chokri Belaid during a demonstration against the Islamist Ennahda movement in Tunis February 23, 2013.

TUNIS (Reuters) - The party of assassinated Tunisian politician Chokri Belaid will ask the U.N. Human Rights Council to investigate his killing because it lacks confidence in the judiciary's handling of the case, its leaders said on Monday.

The secular opposition leader's assassination on February 6 provoked the biggest street protests in Tunisia since the overthrow of strongman Zine al-Abidine Ben Ali two years ago.

"We agreed ... to go to the Human Rights Council in Geneva to request an investigation into the killing of Belaid because we have doubts in the Tunisian judiciary," Zied Lakhdar a leader in the Democratic Patriots Party, told Reuters.

"We believe that the investigation was not serious and there is a lot of ambiguity and doubts," he added.

Mohamed Jmour, another leader in the party, said the Tunisian office of the U.N. High Commissioner for Human Rights had already been informed of the group's concerns.

Tunisian authorities say they have arrested four hardline Salafi Islamists in connection with the killing, but that the gunman who fired the fatal bullets is still on the run.

Tunisia's moderate Islamist ruling party Ennahda has denied accusations by some of its opponents, including Belaid's brother, that it was involved in the assassination.

(Reporting By Tarek Amara; Editing by Alistair Lyon)