Bulgarian and Polish troops participate in a major military operation in the southern Iraqi city Karbala. It was reported that the military forces have encircled the house of a Shiite religious leader, whose bodyguards killed three US soldiers in the night of Thursday.
Media also reported that armoured vehicles and helicopters circled overhead the office and house of the Iraqi Shiite Muslim cleric Sayyid Mahmoud al-Hassani.
Bulgaria's army chief Gen. Nikola Kolev nether confirmed nor denied whether Bulgarian troops are involved in the military operation in Karbala.
A Bulgarian patrol was caught in exchange of gunfire on Thursday in Karbala in what was the first shootout involving Bulgarian troops. No Bulgarian casualties were reported.
However, 3 American soldiers were killed and seven were wounded in the midnight clash in Karbala, US military officials announced.
Tensions have been high in Karbala, south of the Iraqi capital, where there is a power struggle among rival Shia factions. Earlier in the week Bulgarian peacekeeping contingent escaped fatalities as rival Shia Muslim factions clashed.
A nearly 500-strong Bulgarian infantry battalion is carrying out a six-month mission in Iraq, patrolling the city of Karbala, 80km (50 miles) south of Baghdad, as part of a 9,000-strong 22-nation force under Polish command.