GENEVA - About 60,000 people have been killed in Syria since the conflict began in the country in early 2011, according to a study released by the UN Human Rights Office on Wednesday.

Based on datasets from seven different sources, including the Syrian government, the study shows that 59,648 individuals have died in Syria between March 15, 2011 and November 30 2012.

"Given there has been no let-up in the conflict since the end of November, we can assume that more than 60,000 people have been killed by the beginning of 2013," said Navi Pillay, UN High Commissioner for Human Rights, in a statement.

The figure shows a steady increase in the average number of documented deaths per month from around 1,000 in the summer of 2011 to an average of more than 5,000 since July 2012.

Most of the reported killings occurred in Homs, where 12,560 people died, followed by rural Damascus, Idlib, Aleppo, Daraa and Hama.

"We have not been able to verify the circumstances of each and every death, partly because of the nature of the conflict and partly because we have not been allowed inside Syria since the unrest began," Pillay said.

She added that further investigations would be necessary to discover precisely how many people have died, and in what circumstances, and who was responsible for all the crimes that had been committed once there is peace in Syria.

The high commissioner insisted this massive loss of life could have been avoided if the Syrian government had chosen to take a different path.