An Iranian diplomat was shot dead in Baghdad, hours after three Japanese abducted in Iraq early this week were released unharmed.

Reports say first secretary Khalil Naimi was attacked by three men who drove up and shot him in his car near the embassy. The Iranian foreign ministry has confirmed the death, but declined further comment.

Some Iranian foreign ministry officials are currently in Iraq's holy city of Najaf, where radical Shia cleric Muqtada Al Sadr has been surrounded by American forces.

Earlier, Qatar-based Arabic news channel Al Jazeera aired a video showing the release of three Japanese --- two journalists and a aid worker --- who were kidnapped last week. Their abductors had threatened to burn them alive unless the American forces withdrew from Iraq.

Their release was apparently secured by the Muslim Clerics Association, which has been negotiating for the release of  at least 22 people from a dozen nations kidnapped so far in Iraq by various groups. One of them, an Italian, was executed recently by his captors.  

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