A Bulgarian hostage in Iraq has reportedly been executed by militants, while the fate of two other hostages, another Bulgarian and a Filipino, still hang in the balance.

The Arab television network al-Jazeera is reporting that Islamic militants in Iraq have executed one of two Bulgarian truck drivers they have been holding and are now threatening to kill the second one as well. At the same time, the Philippine government says it is continuing efforts to free a Filipino hostage in Iraq threatened with execution by militants demanding Manila withdraw its 50 troops from the country. An execution deadline passed with no immediate word on the fate of the hostage, or a clear indication from the Philippine government about whether it planned to give in to the hostage takers' demands.

Meanwhile, Iraqi security forces in Baghdad, moved in with what authorities say is the start of a citywide crackdown to round up criminals, many of them believed to have been released from jail by Saddam Hussein when he threw open the gates of Abu Ghraib prison just months before the start of the Iraq war.

Hundreds of suspects were reported arrested but not before outbreaks of street fighting and several reported deaths in shootouts.

So dangerous has the Iraqi capital now become that many foreign contractors involved in the country's reconstruction have pulled out. Those who remain, including journalists, often venture out into the city only with the protection of armed guards.

But Iraq's Deputy Interior Minister Hussein Ali Kamal says this dragnet is part of the interim government's new expanded powers to crack down on crime and clean up the streets of Baghdad and other cities, without the involvement of American forces.

Some 140,000 American troops in Iraq have been in charge of security since the fall of Baghdad 15 months ago. In Brussels, Iraqi Foreign Minister Hoshyar Zebari called on the NATO alliance to fulfill pledges made last month in Istanbul, Turkey to help train and equip more Iraqi security forces as soon as possible, and ultimately ensure security is in place so elections set for January can go ahead as promised.

"We are in a race against time and it's a matter of urgency," he said. "We have a serious problem with border control. To hold elections, we need the United Nations to be established in Iraq. The United Nations needs security of its facilities, installations, and personnel so we have made that request."

The U.N. has said elections could not take place if current levels of violence do not diminish.

NATO Secretary General Jaap de Hoop Scheffer plans to present allies with options for increasing the alliance's role in Iraq later this month. The United States wants NATO to become more involved in Iraq, but there has been opposition for doing so from France and Germany, which have so far ruled out sending their own troops to the country.