Shops were shut in Sri Lanka's ethnic Tamil-majority north on Monday in support of a rally demanding an international probe into alleged atrocities during the nation's civil war and an end to reported state-sponsored efforts to change the ethnic balance of the Tamils' traditional homeland.

Hundreds took part in the rally in Jaffna town. Speakers demanded an explanation of civilian disappearances during the 26-year civil war, which ended in 2009. They also demanded the release of people arrested for alleged links to the now-defeated Tamil Tiger rebels and the return of land and homes taken by the military.

A proclamation read out at the rally said Tamil people have faced massive challenges since the end of the war, with U.N. efforts to hold the government accountable for the alleged atrocities proving futile.

"The Sinhala-Buddhist state structure of Sri Lanka is not ready to be answerable, therefore there is no option left for us other than an international investigation. The international community must realize this," the Tamil-language proclamation said.

The government promised the U.N. Human Rights Council in 2015 that it would appoint a local tribunal with the participation of international prosecutors and judges to hear cases of alleged abuses, but it still has not done so. It created an Office on Missing Persons but it has not made headway in resolving the cases of those who disappeared.

The proclamation said the government not only did not keep its promises to the U.N., but it appointed officials accused of war crimes to top posts, referring to the recent choice of Lt. Gen. Shavendra Silva to be army commander.

C.V. Wigneswaran, the north's former chief minister, told the rally that the government since the end of the war has been trying to make the Tamils a minority in the region and end their claim to the land. He said the government has used forestry, agriculture and archaeology projects as pretexts for these activities.

"It is not possible to tolerate such injustices and repressive activities anymore," Wigneswaran said.

The government says it has released much of the military-occupied land back to the owners.

Both sides have been accused of grave human rights violations during the war.

According to initial U.N. estimates, about 100,000 people were killed. The actual number is thought to be much higher, with a later U.N. report saying 45,000 civilians may have been killed in the final months of fighting alone.