ISLAMABAD, June 23 Pakistan's mission in the United Nations has sent an urgent request to authorities here to prepare English translation of Urdu documents related to investigation into the assassination of former prime minister Benazir Bhutto for submission to a UN commission.

The mission has sought two copies of the report of investigation conducted by Pakistani authorities into the assassination which will now be probed by the UN commission. It has said the documents in English should be sent by Wednesday.

The three-member fact-finding mission headed by Chile's UN Ambassador Heraldo Munoz is expected to arrive here in the first week of July to start a six-month investigation.

The FIR of the incident registered by the Rawalpindi city police station and reports of investigation conducted by the local police are in Urdu.

The security plan prepared by police for Ms Bhutto's rally after which she was killed is also in Urdu.

Although the Rawalpindi district police had completed investigation into the incident with the help of the Federal Investigation Agency's Special Investigation Group and submitted a charge sheet to an Anti-Terrorism Court, the FIA has been striving to obtain permission to re-investigate the case.

The government is reported to have sought legal opinion from the law and justice division in this regard.

Five men have been arrested in the case and are being tried.