COLOMBO (AFP) - Sri Lankas president has cited constitutional immunity and refused to go before a US court where he is being sued for $30 million over the killing of a Tamil man, an official said Sunday. A US-based Tamil lobby had filed the case claiming damages from him as commander-in-chief of the Sri Lankan armed forces for the alleged killing of Raghiar Manoharan, a member of the islands ethnic Tamil minority. Under our laws, the president has immunity, justice ministry secretary Suhada Gamlath told AFP. We dont have to respond to such summons and I have written to the District Court of the Southern District of Columbia of our legal position last week, Gamlath said. Sri Lanka is facing mounting international criticism over alleged war crimes committed in the final months of its battle against separatist Tamil Tiger rebels who were defeated in May 2009. The summons on Rajapakse was first delivered to his Temple Trees residence in Colombo where it was not accepted, officials said adding that the court order was later accepted by the justice ministry. Gamlath said under Sri Lankan law the island could dismiss the summons as the head of state enjoyed immunity guaranteed to him under the constitution. The local Sunday Times newspaper said the case was filed when Rajapakse made a private visit to Texas earlier this year.