Sri Lanka's justice ministry has received a summons issued by a US federal court for President Mahinda Rajapaksa.
The summons is linked to three civil cases filed under the Hague Convention by relatives of Tamil victims of alleged extra-judicial killings.
The alleged killings took place during the Sri Lankan civil war.
The petitioners are claiming financial damages under the US Torture Victims Protection Act.
A Sri Lankan justice ministry source confirmed to the Sri Lankan Daily Mirror newspaper that President Mahinda Rajapaksa had received a summons and said the government would not respond to it.
The cases were filed in Washington DC for a total value in damages of $30m (£18.5m).
They were filed by the relatives of student Ragihar Manoharan, Premas Anandarajah - a humanitarian aid worker for Action Against Hunger, and T Thavaraja, the newspaper said.
According to the Daily Mirror, the cases are linked to deaths dating from 2006. Ragihar, the newspaper says, was one of the five students allegedly killed in January 2006 while Anandarajah was one of the 17 Action Against Hunger staff members killed in June 2006.
The Sri Lankan government has repeatedly argued that it has been unfairly criticised for ending a conflict that claimed tens of thousands of lives amid regular suicide bombings of government targets.
It has dismissed as fabricated footage images that emerged of what purports to be extrajudicial killings of Tamils by the military during the army's defeat of the Tamil Tigers in 2009.