Sri Lanka's defense secretary says the government is counting how many civilians were killed in the final months of the country's civil war, but that the number of dead will be far too small to constitute war crimes by the Sri Lankan military.

Gotabhaya Rajapaksa made the announcement Thursday, after the government acknowledged for the first time in August that civilians may have died during the government offensive that eventually ended Sri Lanka's decades-long civil war. Earlier, officials had said no civilians were harmed in the conflict between government troops and the Tamil Tiger rebels.

Rajapaksa said Thursday that the rapid expansion of the Sri Lankan military may have allowed for the admission of a few soldiers who “lack the capacity to withstand the pressures of warfare with the required composure.”

A United Nations report issued in April said tens of thousands of civilians may have been killed due to government shelling of hospitals and other civilian targets. It said the military's actions could amount to war crimes and called for the U.N. to establish a special body to investigate further.