FREETOWN - Sierra Leone's incumbent president won re-election and was sworn in for a second term, pledging to boost the economy of the nation scarred by years of civil war.

President Ernest Koroma got nearly 59% of the vote, beating his closest competitor's 37% in an election international observers described as peaceful.

By getting more than 55%, he avoided a second round of voting with the opposition frontrunner.

Following his win, Koroma called for unity as he was sworn in late Friday.

"Let us, as we celebrate, be mindful that the work starts today and every Sierra Leonean from all political parties, regions, ethnic group, age and religion is central to our agenda for prosperity," the president said. "We must therefore embrace each other as we march forward with action, bravery, commitment, discipline, empathy and fortitude."

Koroma, 59, a former insurance executive, assumed office in 2007. Supporters have credited him with improving infrastructure while critics have said he has not addressed rampant corruption.

"I will make sure the fruits of the agenda for prosperity are equality distributed in every district of the country and enjoyed by all," he said in his swearing-in . The work starts today."

The United States applauded him and hailed the west African nation's democracy.

"This election demonstrates the progress that Sierra Leone has made in strengthening its democratic institutions since the end of the civil war in 2002," White House spokesman Jay Carney said in a statement.

Sierra Leone's economy was gutted by an 11-year civil war that ultimately left 50,000 dead or missing

During the brutal war, which was funded using the so-called "blood diamonds," teenagers were placed under the influence of drugs to provoke violent behavior such as killing, raping and plundering.