NEW DELHI: The National Investigation Agency (NIA) has arrested two key operatives of Canada-based 'listed terrorist' Arsh Dala in an early morning operation soon after they landed at the Indira Gandhi International Airport from Manila, Philippines.Manpreet Singh alias Peeta and Mandeep Singh were both 'wanted' close operatives of Dala and had non-bailable arrest warrants against them for carrying out terror acts, including threats and intimidation, and terror funding for banned terrorist organisations in India.Originally from Punjab, the terrorists had been living in Manila and were nabbed by the NIA team waiting at the airport, the moment they landed, said the agency.NIA investigations had revealed that the accused had entered into a criminal conspiracy to raise funds for Khalistan Tiger Force (KTF), a banned terrorist organisation. "They were also engaged in smuggling of arms, ammunition and explosives for the KTF from across the border."