Chilean to head UN's Bhutto assassination inquiry

* Other members of Bhutto Commission are Irish, Indonesian

* Will not have power to launch criminal proceedings

(Adds date inquiry will begin work, paragraph 3)

By Louis Charbonneau

UNITED NATIONS, June 19 (Reuters) - Chile's U.N. Ambassador Heraldo Munoz will head a six-month U.N. inquiry into the 2007 assassination of former Pakistani Prime Minister Benazir Bhutto, a U.N. spokeswoman said on Friday.

The other two members of the U.N. "Bhutto Commission" are Indonesia's former attorney general Marzuki Darusman and Peter Fitzgerald, a retired senior officer with the Garda Siochana, Ireland's national police force, spokeswoman Michele Montas said.

She said the commission's six-month mandate would begin its work on July 1, but did not say whether it might be extended if the commission felt it necessary.

Munoz was a co-founder of Chile's Party for Democracy and has held a number of government posts in democratic Chile. He was deputy foreign minister in 2000-2002 and has been Chile's ambassador to the United Nations since 2003.

As previously announced, Montas said the inquiry would not be empowered to launch criminal proceedings related to the assassination of Bhutto, who was killed in a suicide attack in December 2007.

"The commission is not a tribunal," she told reporters.

That will make it much less far-reaching than a probe by the world body of the 2005 killing of former Lebanese Prime Minister Rafik al-Hariri, which is intended to lead to a U.N.-organized trial in The Hague.

"The Commission's mandate will be to inquire into the facts and circumstances of the assassination of former Prime Minister Bhutto," Montas said. "The duty of determining criminal responsibility of the perpetrators of the assassination remains with the Pakistani authorities."

She said Secretary-General Ban Ki-moon would inform the U.N. Security Council of the results of the inquiry "for information" and that it would be up to the 15-nation body to decide what, if anything, it does with the outcome.

Pakistan will provide security for members of the commission, Montas added.

Earlier investigations by Pakistan's previous government and the U.S. Central Intelligence Agency accused an al Qaeda-linked militant of killing Bhutto, a staunch supporter of the U.S.-led campaign against Islamist militancy.

Some of Bhutto's aides have expressed dissatisfaction over those investigations. (Editing by Anthony Boadle)