Sri Lanka's ruling party has won a landslide victory in Saturday's local elections but failed to secure control of the capital's municipal council in one of its few defeats.

Officials results released Sunday show Sri Lankan President Mahinda Rajapaksa's United People's Freedom Alliance won majorities in 21 of the 23 municipal councils that were contested in the vote.

The main opposition United National Party kept its majority in the local council of the capital, Colombo, while the Sri Lanka Muslim Congress won a majority in the eastern municipality of Kalmunai.

Sri Lankan government officials said the ruling coalition's large wins in other provincial towns are a vote of confidence in President Rajakapsa's leadership. Mr. Rajapaksa won a second term last year after his government crushed Tamil rebels in 2009 to end a near four-decade-long civil war.

But, Mr. Rajapaksa's coalition also is showing signs of internal strain. Two rival members of that coalition were involved in a deadly gun battle Saturday, in which their supporters fired at each other in eastern Colombo's Kolonnawa district.

The gun battle killed Rajapaksa aide Baratha Lakshman Premachandra and severely wounded the aide's political rival, Duminda Silva, a lawmaker. Three other people also were killed in the shoot out. Silva was in a critical condition in a hospital after having two bullets removed from his head. It was not clear what triggered the fighting.

Authorities imposed a curfew on the Colombo neighborhood but lifted the measure early Sunday.