Lebanon's two main Shi'ite Muslim groups welcomed on Sunday as a "positive and serious step" a military prosecutor's decision to arrest 11 soldiers and six civilians in connection with last weekend's clashes between troops and Shi'ite Muslim protesters that left seven people dead. The conciliatory positions by the militant Hizbullah group and the moderate Amal Movement are likely to help defuse tension between the army and the two opposition factions, which has been simmering since the riots erupted south of Beirut on Jan. 27. The rioting was the worst in the Lebanese capital in a year. What started as protests against electricity rationing degenerated into clashes with troops in mostly Shi'ite areas of the south Beirut suburb of Shiyah. On Saturday, military court magistrate Jean Fahd issued arrest warrants for 11 soldiers, including five officers, and six civilians in connection with the clashes after questioning 120 soldiers and 85 civilians, according to court officials.