GENEVA (AP) — For the second time in as many years, the U.N.’s top human rights body approved a U.S.-backed resolution Thursday calling on Sri Lanka to more thoroughly investigate alleged war crimes committed by both sides during the country’s quarter-century civil war with the Tamil Tiger rebels.

By a 25-13 vote, the 47-nation U.N. Human Rights Council urged the South Asian nation “to initiate credible and independent actions” to ensure justice and accountability in the aftermath of the conflict, which ended in 2009.

Sri Lankan government supporters carry placards during a protest outside the U.S. Embassy against a United States-sponsored draft resolution discussed at the United Nations Human Rights Council in Geneva, Thursday. Pic: AP.

The resolution followed a U.N. report alleging the government may be to blame for thousands of civilian deaths during the military campaign to defeat Tamil Tiger rebels. Like a similar resolution in March 2012, the measure asks Sri Lanka to probe allegations of summary executions, kidnappings and other abuses, but stops short of calling for an international investigation.

Sri Lanka and its allies staunchly opposed the resolution, saying it unduly interfered in the country’s domestic affairs and could hinder its reconciliation process.

(READ MORE: Sri Lanka blocks BBC reports as UN condemns anti-Tamil violence)

The head of Sri Lanka’s delegation to the council, Cabinet Minister Mahinda Samarasinghe, insisted before the vote that the resolution would set “a dangerous precedent” with its “interventionist” aims and could undermine the Human Rights Council’s credibility.

“Today it is Sri Lanka, tomorrow it may be any other country,” he told diplomats.

The Sri Lanka government has argued that its own investigation should suffice. A Sri Lankan commission report, released in December 2011, cleared government forces of wrongdoing.

Rights groups and foreign governments have called for an independent probe since government troops crushed the separatist rebels. Backers, such as the United States, the European Union and India, argued that credible probes into alleged crimes are an important step to heal the nation.

“”The end of the conflict in Sri Lanka provided a unique opportunity to pursue a lasting political settlement, acceptable to all communities in Sri Lanka, including the Tamils,” said India’s ambassador, Dilip Sinha. “We urge Sri Lanka to take forward measures to ensure accountability. We expect these measures to be to the satisfaction of the international community.”

In the end, the Geneva-based council passed the resolution with 25 countries in favor, 13 against and eight abstentions.