The United States said Monday it was “deeply concerned” about civilian deaths in Sri Lanka and called on the Colombo government and Tamil Tigers rebels to end their decades-long fighting. “We're deeply concerned,” spokesman Ian Kelly said when asked to comment on reports that more than 400 civilians had been killed in a “no-fire” zone. “We think that there's an unacceptably high level of civilian casualties. We've repeatedly urged the Tamil Tigers to lay down its arms and allow the civilians to leave the safe zone.” The new spokesman also called on the government of Sri Lanka “to abide by its April 27th statement that combat operations have concluded, and that security forces should end the use of heavy weapons, which of course could cause civilian casualties.”