Iraq blast near Japanese troops

Iraqi police guard the area where the mortar round exploded

A mortar round has exploded in Samawah in southern Iraq, close to where Japanese troops have been deployed.

The blast shattered windows, but no injuries have been reported.

About 100 Japanese troops are currently setting up a camp about 6km (4 miles) outside the town, where a total of 600 troops are to be based.

It is Japan's first troop deployment to a combat zone since World War II, and there is much concern in Japan about the safety of military personnel.

The round exploded at around 0500 (0200 GMT) near a hotel in Samawah housing about 100 Japanese journalists covering the deployment.

Colonel Yasushi Kiyota, spokesman for the Japanese forces, told the Associated Press that Dutch troops who patrol the city were investigating.

PACIFISM UNDER THREAT? Japan's constitution renounces the use of force This has been stretched to allow self-defence troops 1992 law allowed troops to join UN and relief work overseas 2003 law said troops could go to non-combat zones in Iraq PM Koizumi wants to give Japan even greater powers Papers express reservations

Japanese forces were not affected by the attack and would continue their work establishing a base camp, he said.

It is the first attack in Samawah since the troops were deployed in Iraq last Sunday.

Pacifist constitution

The move is controversial because critics argue it could violate Japan's pacifist constitution if the troops are drawn into combat.

Opinion polls suggest that about half of the Japanese public is currently opposed to the deployment.

Japan's constitution prohibits the use of force in international disputes, but the Japanese Government argues the country is entitled to exercise self-defence and the troops will be able to return fire if they are attacked.

Japanese Prime Minister Junichiro Koizumi has argued that the mission is necessary to bolster Japan's role in the international community.

A total of about 1,000 Japanese troops - 600 main ground units and 400 air force and naval logistical support units - are expected in Iraq by March.