An explosion has taken place in a southern Iraqi city where Japanese troops have been delivering humanitarian aid.

A mortar shell was found at the suspected site of Thursday's blast near the provincial council building in Samawa, Japan's Kyodo news agency reported, citing police.

There were no reports of injuries following the early morning explosion, it said.

Police believe the explosion may have been related to a clash earlier this week between police and protesters and to a rocket attack near the council building, in which one person died and six others were wounded, Kyodo said.

Two US female soldiers found killed

The American army announced that one of its soldiers was killed and another was injured in a booby trapped car explosion led by a suicide bomber near one military American base in Balad to the north of Baghdad.

Earlier, the American army announced that the two American female soldiers, who were considered missing after the attack of last Thursday in Falluja to the west of Iraq, were found killed. This increased the number of killing among the American marines to six in this attack.

Thereby number of American soldiers killed since the American invasion of Iraq in March 2003 increased to 1730, according to the figures of the American defense department.

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